Like Espada said, White Owls are not developing Deadly Premonition 2, Swery is directing it but Access is developing it. As for White Owls other commitments, The Good Life is nearly finished, and the Swery+Suda game doesn’t have a publisher yet, so MS could publish it if they acquired White Owls. Besides, it’s not like prior commitments have stopped MS from buying other developers. Ninja Theory, Double Fine, Obsidian, and inXile all had prior commitments when MS bought them; The Outer Worlds for Obsidian, Darth Vader VR for Ninja Theory, Psychonauts 2 and Rad for Double Fine, and Wasteland 3 for inXile, which MS allowed them all to fulfill before they start working on Xbox exclusives.
I agree that White Owls would be a nice get for XGS especially considering that their first game was pretty interesting and I personally liked it a lot. But I really do hope that in this case MS won't interfere in any projects they currently have. Swery+Suda game is a complicated situation because it will probably be a joint development between White Owls and Grasshopper, so if one of the studios will become MS first party in the process, the development and publishing will be tougher unless MS will allow them to work without any interference at all. Unfortunately, as it stands right now, MS is not a gaming media darling at the moment so they have to act really cool headed because any small misstep can result in a huge shit storm against them in the media and it's the last thing they need right now.