In the absence of documentation of how the equity dissipates, it would be assumed not to. In that case, I'm not sure it's dismissable as a technicality: if an early, vital partner has to leave, you have to weigh the costs of buying out their equity stake against current cash demands. When the future of the company is tenuous, the value is small and Guillory surely would have accepted a song for a buyout, just as Walter White took a $5000 buyout for his huge stake in Grey Matter (or the Apple guy); but they may also need that money very much.
If you take the approach of "well [in hindsight] OBVIOUSLY they didn't mean to leave him with that equity", you're effectively giving founders a free option on the shares of silent partners, unfair in its own way.