I remember when i started haxball in 2019 i saw anddy playing on big&futsal, and since 1 year something like that he definitely stopped to play big and he always say its shit, but he say this since he own the BFF rooms, i dont know if you guys remember Futsal public room with super hero powers, like everyone could get bonus and have custom superpower like giant player, fast speed, power shots, so its definitely possible to modify each player proprieties, btw i just did a test in private room, the thing that its hard to push Anddy is obvious for everyone but idk if u guys notice when king push him and anddy start to run he have sort of high acceleration and he get far away from king instantly, i did a test in private room on same map
https://imgur.com/WZIX5bP as u can see logically when i push and he start to run we stay on same distance and same speed, so yes with all these sus things if he added tankness to himself he also probably added some speed like +3-5% of speed so we cant rly notice it.
Also some people heard about private rooms, some teams refuse to play out of their own host and sometimes the room feeling rly strange, if u want community to get better without corruption like this, we all should use GHS rooms hosted by people that are not a competitive players themself