Composite Two CSI Camera stream into single RTP stream

Thank you so much! That helped me come up with a working pipeline. Now i need to receive it on a standard linux box.
I tried

gst-launch-1.0 -ev udpsrc port=5000 ! queue ! application/x-rtp, media=video, encoding-name=H264 , width=2560, height=720, framerate=30/1 ! rtph264depay ! h264parse !decodebin ! autovideosink

but received this and no video window:

Setting pipeline to PAUSED …
Pipeline is live and does not need PREROLL …
Setting pipeline to PLAYING …
New clock: GstSystemClock
/GstPipeline:pipeline0/GstCapsFilter:capsfilter0.GstPad:src: caps = application/x-rtp, media=(string)video, encoding-name=(string)H264, width=(int)2560, height=(int)720, framerate=(fraction)30/1, clock-rate=(int)90000
/GstPipeline:pipeline0/GstRtpH264Depay:rtph264depay0.GstPad:sink: caps = application/x-rtp, media=(string)video, encoding-name=(string)H264, width=(int)2560, height=(int)720, framerate=(fraction)30/1, clock-rate=(int)90000
/GstPipeline:pipeline0/GstRtpH264Depay:rtph264depay0.GstPad:src: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline
/GstPipeline:pipeline0/GstH264Parse:h264parse0.GstPad:src: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0.GstGhostPad:sink.GstProxyPad:proxypad0: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstTypeFindElement:typefind.GstPad:src: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstH264Parse:h264parse1.GstPad:src: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/avdec_h264:avdec_h264-0.GstPad:sink: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstCapsFilter:capsfilter1.GstPad:src: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstCapsFilter:capsfilter1.GstPad:sink: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstH264Parse:h264parse1.GstPad:sink: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstTypeFindElement:typefind.GstPad:sink: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstDecodeBin:decodebin0.GstGhostPad:sink: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline, width=(int)2560, height=(int)720, framerate=(fraction)0/1, interlace-mode=(string)progressive, chroma-format=(string)4:2:0, bit-depth-luma=(uint)8, bit-depth-chroma=(uint)8, parsed=(boolean)true
/GstPipeline:pipeline0/GstH264Parse:h264parse0.GstPad:sink: caps = video/x-h264, stream-format=(string)avc, alignment=(string)au, codec_data=(buffer)01424028ffe1000a67424028965401400b7201000468ce3c80, level=(string)4, profile=(string)constrained-baseline
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/avdec_h264:avdec_h264-0.GstPad:src: caps = video/x-raw, format=(string)I420, width=(int)2560, height=(int)720, interlace-mode=(string)progressive, multiview-mode=(string)mono, multiview-flags=(GstVideoMultiviewFlagsSet)0:ffffffff:/right-view-first/left-flipped/left-flopped/right-flipped/right-flopped/half-aspect/mixed-mono, pixel-aspect-ratio=(fraction)1/1, chroma-site=(string)mpeg2, colorimetry=(string)bt709, framerate=(fraction)0/1