Welcome to D.C.!!
I reckon you could try it, but brown sugar would likely work a little better. You could also use white sugar. The applesauce might be good. Never heard of it but that doesn't mean you shouldn't try it. Who knows? It might be quite good. The trick to using a vinegar sauce is to use it sparingly. Good luck and let us know how it turns out.
sounds like a good idea...add brown sugar to taste on top of adding the apple sauce... that is if you're finding the apple sauce isn't giving enough sweetness to the vinegar.. i'd even get more adventurous and add a hint of spice/hotness
let me know how your sauce comes out.. I'm curious on your results!!
Are you using white vinegar? i'd probably use apple cider vinegar and cut it with some apple cider...and maybe some maple syrup. But, I have a surplus of maple syrup since we collect sap in the spring and evap it.
Welcome to DC! I'd also be curious as to how the sauce turns out and what you ended up using.