How long has it been in primary? Or, how long did it take to go from 1.055 - 1.010? Giving it more time might do the trick (And the lacto might not be done either).
If it's really stuck, I'd just throw another higher attenuating yeast. I typically just use Safale US-05 or the super yeast. US-05...
Well, it will be hard to tell if anything will go wrong because of what happened. However, you've exposed the beer to a lot of oxygen after the fermentation which might cause oxidation.
I'd suggest just continue as normal. Many beers that I thought I screwed up ended up very good.
To be honest, I should have said "Max ABV". I didn't take a reading after the sour mash and before the Sach pitch. This is probably the only way to have truly known the ABV (Short of sending a sample for analysis).
Since my sour mash was made by pitching uncrushed 2-row, Lactobacillus...
Got my first taste of this beer from a hydro sample. It's fantastic!
I'll post a picture later today, but this ended up around 3.9%ABV and the perfect tart/sour level.