Pretty sure Katoa had a few errors last round so that impacted his score somewhat. Remember he crossed for a meat pie the game before as well so 40-50 will probably be his average unless he gets some attacking stats.
As for who to play, I couldn't really give you too much to go off as Fui's minutes are up in the air as are Musgrove's. Katoa probably has a more secure role so might be the safe bet.