This happened to Slotland some time ago also. Someone sold Slotland on ebay – but all it was is a mirror front and it had an affcode imbedded.
That is criminal.
It is up to Jeff if he wants to go after it now or later – but now seems more fair since the real criminal is still holding the domain. Later it will just be the sucker.
As for just mirroring the wagerprofit site to bring in new affs – this is done widely. One should always get the permission of the aff program before mirroring a site. Many programs approve, some will not let you use their copywritten site for your purposes.
Personally I see no harm in this and I have done it too. It is just good business to make sure it’s ok and ask first.