I understand, of course, that they might be very busy as they lead a few bounties. but i think you must be able to count your time and posibilities for that. if you cannot handle it - than do not take it, it is so simple. also there are some good managers leading much companies and having time and patience to face everyones issue. at least can explain where mistake was. this is important. Anyway, the best way as someone above said - not to participate to campaigns with bad managers, even if ico you think good.
Yes, you have the choice to avoid them.
In any case you have already joined and felt that the manager is lacking with something, always be polite and respectful because no one can fix the issue but only him/her.
Also, participants should be obligated to always check the status of his/her records. It is better to report a problem early than late.