Paul had no wife. Is he disqualifying himself?
Or does it mean no man should be made Bishop who has had more than one wife?
It means that an "episkopos" can't have more than one wife. It could mean that he can't be married and then divorced. It could mean that he can't be married to two women at the same time. But that's not the point.
Does the Catholic church allow bishops to be married, to have a wife?
That's the point. The biblical "episkopos" is not the same office as the Roman Catholic office of "bishop" because the scripture clearly indicates that being married does not disqualify one as a "episkopos".