As far as recoating the bottom would a couple of coats of Interlux 2000/2001 barrier paint do the trick?
Maybe so, maybe no (hard to say without pics). Depending on how the original gelcoat was removed, and how deep the stripping went. If they used a power planer, then the hull's definitely gonna need to be faired first -- additional layers of glass may also be in order to restore hull thickness. If they sandblasted it off, then fairing's probably going to be in order. If they carefully sanded it off, then the barrier coat will probably be able to serve as a fairing compound (but a pretty expensive one.)
If it were me I'd fair, barrier coat, then paint. If the boat's not going to be left in the water (i.e., dedicated trailer sailer), then the barrier coat is probably overkill.
A preliminary question would be "why'd they strip through the gelcoat in the first place?" Accidental? Blisters?