think it's safe to say anything in the chinese version is non-canon.
otherwise they'd be in all versions of the game.
there's a reason certain bosses don't exist in the current version of terraria.
guess this means the chinese version won't be involved with crossplay, if that becomes a thing.
Edit: also, i thought you were referring to the actual santa tank boss... i had no idea there was an actual tank mount, i just found it on the wiki.
but it says it's master mode only?
i thought master mode only had those gold boss trophy things... had no idea it had exclusive drops other than those.
was it always like that?