With my own further attempts this seems like a job that is going to involve some masking and regional adjusts, even just between the 2 faces. Doing it photo wide there is a lot of improving one area of the photo but then ruining another.
Thanks for the attempts and advice!
What application are you using? I can tell you this stuff is much easier if you have a graphics tablet, especially one large enough so that your hand motion invokes a similar amount of cursor motion. If you're using a mouse, make sure any acceleration is turned off. You may need to adjust its sensitivity as well.
The color pallet is a bit weird here. Ignoring the under-exposure, the reds are still quite saturated.
My thoughts are that you probably need a few things. Toning down the exposure on the faces won't work with a typical brightness adjustment. You'll need something akin to channel mixer in photoshop to start with. You'll need to make some regional adjustments to the faces to bring back depth as well, if you want it to look good. Otherwise you will most likely just end up saturating them.
If you do any work on the faces, you'll need to be careful to mask out the lips. They're already quite saturated and probably limited in detail.
I would probably ignore the shadow portions that are completely gone. You can balance them to a slightly more neutral black if you like, but you should avoid making them look too processed.
Note that if the information just isn't there, some of this kind of work becomes a bit illustrative in the sense that you end up repainting shadows and things. That's considerably more difficult.