IMO, that's probably the best thing. Seriously, I would send the barrel back and have them do what ever it takes to remove any signs of the brake.
Again, IMHO, I don't believe there is any caliber that the contender will safely shoot that requires a brake. I currently shoot a 375JDJ and know some guys that shoot the 444 Marlin and 45-70 in the contender and none of them use muzzle brakes. Sure there is a little more recoil, but not to the point of being unbearable.
However is the brake is what you really want, I would have it replaced by Thompson.
That's why there are so many choices and selections.......Everyone has their own preferences and as the old saying goes, "To Each his own"
Good luck and good shooting.
HBL