That form says specifically not to use if I don't know they were cheating though. I didn't play with them, so I don't know if they were cheating.

There's a drop down menu. For other reasons for the report.

Yes, but I can't use any of those options because of what they ask for. "Report a player from the Roster" - I can't do that because it was yesterday. "Report a player from last activity" - I can't do that because I left the match immediately and it didn't show up in my activity. "Report a Destiny player on Bungie.net" - says to go to game history, see above. "Report a clan profile" - I didn't see their clan, only their names and messages in text chat. "Report malicious text chat" - it asks you to go to their platform's profile, which I don't know.

If you go to their Bungie profile (typing in the vile name) and look at the "about me" page of the profile it'll list the platform accounts connected to it.

Didn't know I could just type their player name into the search option to find them. I will try that, thanks!