We can now assume he is from the MU, yes? Absolutely all signs point to it:
- MU Lorca has history with Burnham, having killed her in the MU. Our Lorca conventiently has a plan to presumably get access to the most powerful ship in the MU, that involves our Burnham, a person who our Lorca brought onto his crew against Starfleet's wishes and, I believe, had her prison ship detoured to him in the first place?
- All the dangerous weapons he was keeping in that room of his.
- Sleeping with female crew members (Landry), etc. Something very MU about that!
- He told Mudd that he watched his old ship blow up, all hands lost, claiming he did it himself. MU Lorca's ship was destroyed, MU Lorca being known to have escaped prior.
- The Admiral made note that the sex she had with him wasn't what it used to be, putting it down to PTSD, but never obviously assuming it could because she was sleeping with a wholly different man.
- Sleeping with a phaser under his pillow was played as a PTSD symptom, but one would assume ALL MU captains would keep phasers under their pillow out of habit.
- There was obviously the screengrab taken from Episode 9 which showed a Captain's Override in the destination coordinates just prior to Stamet's accidentally taking them to the MU.
- When speaking to the crew in this episode about his work on discovering the spore drive could possibly take them to alternate universes, he specifically said that Stamets had said he wanted to explore those ideas following the end of the war, something we know Stamets said the exact opposite of.
- Takes Culber off of treating Stamets, now he's in the MU. Culber himself says he is the best person to be treating Stamets, but Lorca takes him off his care anyway, presumablynhoping Stamet's doesn't recover now.
I mean, at this point, it's almost obvious, isn't it?