As far as I can see it, the only thing that needs to be explained are the physics of
why the portal sucked Dalton in. Here are the events that lead to his appearance in the DV.
- Party arrives on the wing of the Blackbird, after escaping their prison cells and reclaiming all of their possessions.
- Party finds way to the wingtip, where Golem Boss appears out of a "summoning" portal, seemingly of its own accord. Battle ensues.
- Party either defeats Golem Boss or he chickens out, depending on player's actions.
- Dalton scrambles from the Blackbird in the upgraded Epoch.
- Party leaps from Blackbird onto Epoch. Battle with Dalton commences.
- Party defeats Dalton. Dalton attempts to summon the already defeated Golem Boss.
- Summoning portal appears, but with no Golem available to bring forth, claims Dalton and whisks him away to another dimension. Later ends up in the DV through yet unproven means.
I'll leave the why and how aspects of this to someone a bit more, um, dedicated?, to the Chronoverse. But that's the skinny on Dalton's mishap.
To answer the original post, Lavos had little to do with Dalton on this one.