I'm not an expert. But
imo pre-publication would make me think of loose pages, unbound, not cut uniformly, something with notes, corrections, etc in it. Again, I'm farrrrr from being any type of expert. It does however look like a 1st Ed.
DMG to me
It also looks like it's held together with 2 rolls of tape, a tube of superglue, and who knows what else. Looks moldy and has obviously been wet. It looks like crap and probably smells like it too!
I wouldn't pay $5 for it. Not even if Gygax himself had farted on it (sorry in advance if that offends anyone.)