Can I "re-caramelize" meat after a failed braising attempt?
I gave it a shot! I took the oxtails out and seared them in a cast iron pan underneath the broiler in my oven. Once they were pretty much blackened on all sides, I dropped in a bit of the stew and simmered it down very briefly using residual heat from the cast iron. It was a surprise how quickly it infused with the caramel flavor from the meat. I added the reduction and meat back to the original stew and it has a decent, robust flavor like I'd hoped. Not ideal, but a good way to compensate for expenses in "cutting corners".

The one downside is that my "fast braise" in the cast iron seemed to have diminished the seasoning slightly. I rinsed and wiped the pan dry then coated with some oil and put it back under the broiler briefly.