I wouldn't go for the collagenase injections myself.
Tendons are made of collagen and are very close to the Dupuytren's cords. I'm sure Xiaflex has been thoroughly tested but probably not in climbers. Minor damage to the tendon wouldn't be noticed in most people but for a climber it might be disastrous. Have many climbers had their DC done this way?
I might consider a Needle Aponeurotomy if my DC was at an early stage and I wanted to get back onto rock asap.