Hurl Through Hell works on no boss (it works on heroic minibosses too). Against bosses you need use dps.
For dps, with the pact you have no choice but to deactivate it, otherwise you will be healing them all the time. Force damage can be changed to piercing by the tainted scholar's "penetrating blast" stance. This allows you to do significantly more damage to them than with force. I'm surprised no one told you this. In heroics this is the most effective way to kill golems, and good for legendary too.
Don't forget going back to "faltering blast" after killing the golems.
Ruins work against golems, but be careful with intensified ruin... I hope you are a tiefling that can remove their immunity to fire just long enough to cast the ruins. Arcane tempest works on them, but meh, it's force and golems eat a lot of that damage. Penetrating blast is still your friend.
Anyway, golems are a nightmare for warlocks. Also for other casters without bypass, but especially for fire walocks.