Below is the solution for your case(run TLT 3.0 in a TLT 2.0 docker)
$ docker run --runtime=nvidia -it -v /var/run/docker.sock:/var/run/docker.sock nvcr.io/nvidia/tlt-streamanalytics:v2.0_py3 /bin/bash
root@a14bd3e33d2d:/workspace# pip3 install nvidia-pyindex
root@a14bd3e33d2d:/workspace# pip3 install nvidia-tlt
root@a14bd3e33d2d:/workspace# docker login nvcr.io
Username: $oauthtoken
Password: your-ngckey
root@a14bd3e33d2d:/workspace# tlt gazenet dataset_convert …