Sorry to hear about this shitty situation. Your car sounds like a beauty
I would ask your adjuster what information was brought forth to make them change their tune about fault. The car should have absolutely been dollied. The driver should have known this. He decided to tow the car without the wheels secured properly. Seems pretty cut and dry to me. Maybe he is telling ICBC that your buddies made him tow the car as is. Without being there yourself when it happened it's hard to say who said what. With ICBC, it's all negotiation. Their trying to find reasons to NOT pay your claim. You need to find out those reasons and build your case. Either way, one of the garage policies will cover the damage.