Warranty work question



So I need some advice. Upon a recent oil change, I've come to find out that my DCT is leaking. I have an extended warranty through Assurant that I purchased prior to my factory warranty expiring.

My question, is it best to bring my car to an indy shop or bring it to BMW? The reason why I ask is these extended warranty companies can be a real pain to deal with as far as what's covered and what's not, and BMW generally charges a higher rate than an indy shop, so the more reason for the warranty company to try and deny coverage. Plus I'm trying to circumvent BMW trying to hit me a diagnosis charge when I already know the issue at hand.

In addition, my DCT leaking does not fall under complete mechanical failure. They might try to hit me with the DCT related seals being a wear and tear component. I'm just a little unsure how to proceed, I generally don't like to keep my cars out of the factory, but the M is a little harder to let go, hence why I got the extended coverage.

Your thought, please.