the big question is why alert hezbollah intentionally? are they not our enemies?

To me it shows how powerful hezbollah is. If they we're inconsequential, what would we care if they were harmed? Further, if they were weak we wouldnt care if they viewed us as partially responsible. Maybe we have added their performance in syria to their performance against Israel and have decided that we would rather not kick thats hornets nest at this time and threw them a bone in the form of this intel.

Are we knowingly siding with sunnis and accepting their AQ links because the geopolitical threat of a shia/persian victory is worse?

It seems possible to me.