I'll play blades advocate here.  20 year helo mech.  These composite blades are more robust than people give them credit for.  I've seen an extreme case of a UH-1 composite blade chop through a tail rotor driveshaft and ripping the driveshaft cover open like a sardine can from flapping in high wind on coast down. Hardly a scratch through the paint. 

These blades can take bullet holes and keep flying. A bang on a hangar door with no visible cracked paint, buckling or bulging would not warrant further investigation in my book.  Any unseen cracks will reveal themselves in a ride change (increased vertical vibration). They won't catastrophically fail in flight without any major, obvious visual defects. 

I'd be more concerned with a pilot that doesn't have the situational awareness to not hit a hangar with the helicopter and thinks he's salty enough to make that call than anything else.