My experience dealing with amp techs is that they must have knowledge and great a ear. And every single great amp tech that mod, build or service amps that I've met has this.
Playing technics and style, not a must. It helps a lot, of course... but unless if it's impossible to get someone else to play the amps for him, the tech can go a long way without being a good player.
Mark Cameron is a phenomenal player, and he uses that to his advantage. But it's only because of his knowledge and great ear that he can do what he does.
On the other hand, Jose Arredondo and Frank Levi couldn't tell the difference between a D or an A chord, and they've crafted some of the most amazing tones to this date.
Again, being a shredder for sure helps the process, but it was never a must.
PS: My apologies for not mentioning before, congrats to all the ones involved with this amp, it does sound amazing!