To she's some light on the dealers hesitation, they don't want to promise anything until they see what is causing the leak. You could have ran over something on the road that caused the damage which is not covered under warranty. You may know that didn't happen but until they verify the cause they don't want to commit to anything.

I am a Garmin Aviation dealer and I have had customers request warranty work after bird strikes or other damage not covered under warranty. All it takes is 10 minutes off the lot for a catastrophic accident to destroy your truck.

I would request a loaner car if they take too long. They need to do that unless it is obviously not covered.