That tub can be replaced for less than $2K. What kind if acid, for pity’s sake?
Most likely, the PVC plumbing was destroyed. The tub is probably fiberglass/frp which is impervious to most corrosion .
It could have been Muriatic acid they use that in pools.
Maybe if it's inflatable. If it's a "real" hot tub by a reputable brand, the no frills basic model purchase price start about 5k and go up from there. If you can't install it yourself, tack on another few thousand. I could easily see 14k for a really good tub. Granted, that's the high end, but I suspect Bannon wasn't renting a cheap place.