From your description of the loss it sounds like it should be covered. An insurance company providing coverage and the trailer getting fixed correctly are two entirely different things. Please don't forget that.
Your most important job once coverage is afforded is finding a reputable repair shop. Once you find that shop, trust them to do their job. Let them know you'd be happy to assist with any claims-related issues but don't try to control the repair.
50/50 as to if they repair or move forward with a total loss. If they decide to total send me a PM and I can give some pointers on how to maximize the offer.