once u go into the raid.. the recommend will give you hint about what movesest the kygore boss will have. (diff pple diff.. becos everyone acc has diff pokemon or powered up pokemon)
for me.. if the recommand appear Groudon first. very obvious. 100%.. boss is thunder kygore... If appear kygores n raikou.. its blizzard kygore.. if appear Venasur n Aolan Exguttor.. it's hydro pump kygore.
Btw, what is mewtwo good for? Have never seen it being recommended for any raid battle
Mewtwo is good for generalist. Provided the boss dosent resist his move or boss is not doing super effective damage to mewtwo.
Regard to why its not being recommand for any raid battle... hmm.. if you understand the system. you will know why.
there are or seems to have certain criteria..example.. the game always recommend pokemon that will hit either effective or netural but good enough damage to the boss while having resistance against them.
hence bring back to first point. ie Thunder .. they will recommand u groudon.. becos Ground resist thunder.. n your groudon Solarbeam will hit kygore hard. Kygore afraid of grass.
that's why hydro pump boss.. if u have alot venasur or exguttor in ur acc. they will recommand grass.. becos grass hit kygore hard n grass resist water.
Blizzard kygore they recommand raikou n kygores himself.. becos Raikou does good damage n take neutral damage to blizzard.. Kygore.. being water typing.. resist Blizzard... n if your kygore has thunder .. thunder hit water hard.
long post but.. ya something like that.. sorry.. my english very poor.
as always..
but i hope it helps. somehow.