julian As suggested by you, searching the URL worked,but I still have one problem and one query-

1. Peertube videos(from tilvids.com) don't start playing. In mastodon and misskey, the hls fragments(~200kB) are fetched but in nodebb, it seems that the entire file is fetched (~150MB) and so playback dosen't start. I tried with two different videos from tilvids.com and got the same result in both cases.
2. Can peertube videos be played only by searching or will they also play if a remote post from a peertube account (like thelinuxexperiment@tilvids.com )contains the video and that post comes in my feed?

ska just enabling federation should do the trick!