They don't come out and say specifically what they're doing, but:
> I have to accept the new terms to continue paying for it, which we have to do to keep legally using Unity, which we have to do to finish our game – because by this point we’re trapped in their platform to the tune of 5 years’ work.
And:
> The only difference with a released game is our recourse: instead of having to abandon development of our game, we’d just have to abandon the game – never patch, never update. Which sucks for players almost as much as it sucks for devs.
It sounds like they're too deep into developing their current game for switching engines to be feasible, so they're presumably going to agree to the new terms and complete development using Unity, release the game, and hope that Unity's current and future terms don't end up being too onerous for them.
