Let the process play out first.

Also read the Specialized warranty and see what the exclusions are. If nothing in the written warranty excludes impacts, then they can't add that rule after the sale. Also if there is specific language saying "does not cover impacts" they have to prove it WAS an impact to deny the warranty.

If the LBS guy is the one telling Specialized that the bike was hit, ask what qualifications they have to make that determination.

I'd also go look at the bike RIGHT NOW and have them show you the damage. See if you think it happened after you dropped it off.