So at the end of the game we had someone who was one space away from their 4th mutation card. The game ended and we began counting up end of game points. His other mutation cards and the viruses he had in a couple of zones pushed him through that space.
So, can you still get a card at that point? Or no?
No. You arent moving on the track during end scoring, the game is over. Also you arent earning VPs as per in game scoring, you are merely totalling. Further, End Game scoring specifies points on the VP track plus extras, explicitly defining those extra points as not being on the track.
Althese semantics and mechanical differences separate your final totalling of score from the during game earning of VPs and moving on the track.