The DMCA can be used to put a fire under them to file a DMCA counternotice, at which point the whole issue with their hosting provider is done and you are down to the basic question of are you going to file, litigate, and win an actual copyright lawsuit on a timeline and at a cost that leaves you with a viable startup.
Depends who is hosting their documentation. Under the DCMA, hosting providers are obligated to take content down when they recieve a valid takedown notice (They can put it back up when they get a counter notice).