Here is my Reddit post of how to get out of forced Spectator mode in comp. There is also a video. It seems to be tied to bounty completion and simply opening your pursuits tab will put you back in the game. I've lost games while playing solo due to other players not knowing how to get back in the game. It's frustrating losing points through no fault of your own. Hope this helps people who are having the issue. https://www.reddit.com/r/DestinyTheGame/comments/cbvrth/how_to_get_out_of_forced_spectator_mode_in_comp/?utm_medium=android_app&utm_source=share
I also found the other day while I was in a strike and "stuck" in a loading area between zones that going to my pursuits tab allowed me to move again and cqtch up to my fireteam. A couple bounty completions popped up at the same time as opening the pursuits so it may be tied in together.