Pretty sure it's definitely Doom. He absorbed some Power Cosmic at one point in the issue, and Doom-bots don't have magic.... during a scuffle with Skaar Doom got his hand chopped in half, then magically stitched it back together before pwning Skaar with a spell that reverted him to his weaker alter-ego.
"The man in the metal suit" - Doombot
"Wolverine sniffed him out and determined he was the real Doom" - Doombot, or so I hear
I mean, if it really is him, props to Bruce and I'm glad that Doom isn't treated like frikkin' Starlin Thanos all the time.