I don't know of a simple, accurate way of measuring how much you've oxygenated the wort, but you should be able to control the attenuation via the use of camden tablets. Just start taking hydrometer samples once fermentation slows down, and when you hit your desired FG, add the camden tabs to kill the yeast.
It seems to me, that you might not need this (IMO). With the hotter mash and the less attenuative yeast, you're likely to have another similar FG again. you could always cold crash the primary once you near the desired FG. Then Keg it an keep it cold. It should take quite a while to dry out if you keep it cold.
"let me be the first to welcome our new insectile overlords"
On deck: Breakfast stout
Secondary: American Pale Ale
Kegged: Imperial red ale, Breakfast stout, Chipotle Irish red ale, Biermuncher's C3C cream ale