Of course you can sign those 4 for $7.6m. It will take about $1.4m for Volkov and Joseph, leaving $6.2m.
So $1.9m to Cernak and $4.3m to Cirelli, or some other combination. If Cernak is worth more than that (unclear), maybe you only get one year at that number and have to work it out with him again next year.
The issue is that only leaves us with 19 guys on the roster. Paquette's cap hit is enough to cover a little more than two bodies on minimum contacts, so we probably deal him and bring up two more AHLers. (Even better would be dealing Coburn, but I doubt we find a buyer.) That only gets us to the league minimum (20 players), which is not ideal. There'd still be a few hundred $k lying around, though, and JBB could get Cirelli for a bit less if the deal is only one year if he wants enough room to add one more minimum contract. Not easy choices for JBB, but no intractable problems.
Another thing to bear in mind is that there are going to be special Covid roster rules due to the inability to send guys between AHL and NHL, so JBB might use that to finesse our lack of bodies problem.
As an aside, I am f'in THRILLED there's likely going to be a season. We have the best team in the league, hands down. And even if we're a little weaker than last year, we're still going to be awesome. Would be a crying shame if we didn't get to see them on the ice.