Jetson Xavier NX Deepstream

I have been trying to run the pre-trained models from the Transfer Learning Toolkit. I keep getting the following error trying to run PeopleNet:-
ERROR: Deserialize engine failed because file path: /opt/nvidia/deepstream/deepstream-5.0/samples/configs/tlt_pretrained_models/…/…/models/tlt_pretrained_models/peoplenet/resnet34_peoplenet_pruned.etlt_b1_gpu0_fp16.engine open error

Furthermore, on trying to set up TLT on Jetson Xavier NX, I didn’t find any matching drivers here:-
https://www.nvidia.com/Download/index.aspx?lang=en-us

What is the best way to resolve this issue? I’d like to run other models like YoloV3 but it requires TLT as well.

Running deepstream-app with sudo fixed the engine open error.