An acquisition seems to be the logical outcome because if the team is going to be working at Google then that raises the question of what's going to happen to the ruba.com site. It doesn't seem plausible that the project would just be abandoned because I think it's reasonable for the owners to expect some compensation for the work they've done.

It seems like a pretty meritocratic way to earn a bigger pay raise than you'd normally get.

It's also a common strategy for someone in an organization to make a big vertical leap or move across the organization in a way that would be nearly impossible internally. Basically, an infrastructure engineer leaves and comes back as a VP of Product for social wizardry.