I just checked the alliance of a recent opponent (I like to look at other teams to compare) and noticed several members who are high ranked on the leaderboard. However, 5 other members should be on the LB based on trophy count but are not.
So it appears that they are flagged cheaters - able to join alliances (and donate ill-gotten DNA) and presumably, in between tournaments, among the rest of us. At least that’s the perception.
If anyone cares, I have names and numbers but will of course not post them here. It’s just disappointing that cheaters are apparently able to abuse the system - but that’s what cheating is, right?