I have used your file and get the same error message.

Here is the video: https://streamable.com/vkav1

In the console I also get the following error message:

int FFMPEG::open_encoder(const char*, const char*):
check_frame_rate failed /home/spc/cin-test/test.proxy2-mp4.m2ts
failed=1 canceled=0
int ProxyRender::create_needed_proxies(int):
Error making proxy.