I have also never heard of Tom Holland being in Avengers: Doomsday.
This isn’t even a negotiating tactic - I’ve heard since last year that it’s purely to ensure parts of the cast get screen time in Doomsday, before “heavy hitters” like Tom Holland, Elizabeth Olsen, Hugh Jackman, Ryan Reynolds, Benedict Cumberbatch and so much more take center stage for the ultimate finale movie.
Doomsday is an Avengers movie but it’s just the appetite before Secret Wars.