had the rear subby heelboard front mounts replaced with the repair panels today, and when i went to fit the beam axle one of the bolts wouldn't screw in. upon closer inspection the captive nuts thread is damaged

my question is: what is the thread size of the nut and is it possible to get a tap for it to try and re-tap it? if not is it possible to dril the nut and re-tap it to m6/mate?
cheers