Transfer Case Drain Plug completely seized

When I first purchased my 99 XJ, I changed most of the fluids. Transfer case fluid included.

I recently noticed a weep from the transfer case fill plug and attempted to remove it to put the new sturdier NAPA plugs on there. I hand tightened it and then gave er a crank with the ratchet so I know they werent over tightened when I first changed them. Never gave me any issues two month ago.

After breaking a ratchet, melting the threads with a torch, and hammering two larger sized Allen sockets into it, I’ve given up trying to open it back up.

Anybody have any suggestions left? I don’t own a welder or know how to weld. so weldings out of the question unless I take it to a shop.