No.

What if they offer to release Melkor in exchange for him coming back to Valinor for the parole hearing and then, get this, are not even actually planning to parole Melkor?

...they can keep "hope Sauron doesn't think of the possibility that Valar might have learned to lie" in reserve.

They will consider other solutions. 

They consider for a while and then remember to inform Elspeth that they are considering and that it might take a long time by human standards! To avoid a disconnect in expectations caused by Elspeth being an incarnate!

Okay, ballpark how long?

...as long as it takes to come up with a good solution? This is a hard problem. It might take a really long time to come up with a good solution.

Well, they could discuss things with the peal on the network but they disabled wizardry so actually now they can't.

They are not enabling wizardry again, Sauron could break Melkor out.

They can't be more selective about it? ...And this might not even stop someone from being summoned out of Valinor from elsewhere.

Well that's terrible what can they do about that.

They did manage to stop Elspeth from teleporting by sorcery that one time, that thing might work.

They are already doing that thing really hard at Melkor so learning wizardry himself doesn't let him leave but they're not sure it works against summoning, is there a way to check?

They could do it to someone else and Boots could try summoning them.

Okay! They'll ask for volunteers.

If that takes a while somebody from the peal can just do it, it won't take long.

It might take a while, how about someone from the peal comes to do it.

Okay. Elspeth will be right back, since she can't summon somebody from here since they disabled wizardry.

Pop pop okay they're going to try to summon Elspeth in ten minutes and the Valar should try to stop that but only until Elspeth says to let her go.

They can do that!

The summon doesn't work.

The Valar are pleased! It means Sauron will not be able to fetch Melkor who is very locked down. They let Elspeth go.

She pops in to inform Warp that the Valar have not e.g. decided to keep her forever or something, then comes back. While they are thinking of their good solution there is a wizard Sauron in a science world on an inhabited planet, so the peal is probably going to do something fast if they can think of anything, even if the Valar can't help that quickly. Do the Valar have, like, relevant resources of which the peal should be aware.

If they bring Sauron back here they can try to keep him from leaving again. That's about it.

Yeah no if Sauron proves portable he's gonna die.

Has he actually done anything?

Well, "ran off to Warp, while Sauron" is not super reassuring by itself, but unfortunately most of the people they could quiz on the timeline are also Sauron and therefore dead now. They could as a formality ask a Thuringwethil or something when Saurons start doing things.