OP received a valid negative feedback from Badbear which is the only feedback anyone should consider bearing in mind that Badbear is the admin. Rest those who left negative feedback don't have any proof/evidence and hence their feedback doesn't make sense.
I don't get if one has already received a negative feedback from the admin or a default trust member, why do other members too join the league? Does it improve or make his trust rating more valuable or trustworthy? I don't think so and find it weird ways of entering the default trust system.
If only one user left negative and he/she is removed from default trust list, negative rating will change to neutral rating. So to avoid it, two or more or DF users leave feedback.
OK but in this case Badbear may not be removed from the default trust list so here the other negative ratings don't make sense.