If the hole is already threaded, how about putting an Allen-head bolt into the hole, torque it snug, and secure it with red LocTite. That will minimize the distortion and possibly prevent a crack or a break from getting started. Good luck!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!