No. Worst case scenario is a buyout or retention on Johnson. Buying out McDonagh is a nonstarter.

The buyout costs ain't much in 21/22, it's 22/23 that the buyout cost is higher 4.7, and 5.7, and 5.7 for McDonagh alone in for three years starting in 22/23.
Palat and Killorn with their M NTC might be the easiest trade moves and most cost efficient.

Getting rid of Johnson alone won't solve your cap problem, unless Stamkos or Kuch feel like sitting out another year.

Palat or Killorn, it's not as hard as you make it out to be.

I don't think it'll be as easy as you think it will be.

If Skjei is taken by Seattle, Palat would make an excellent one year addition to the Canes.

What would the cost be?

Yeah, agreed. No chance Tampa does this. McD is likely moved to Seattle with a small sweetener, Johnson is traded with small retention or bought out, and Tampa trades one of Killorn/Palat and maybe Rutta. They have enough to keep everybody else except for either Coleman or Savard. Since McD is in Seattle, the emphasis is likely on shoring up the defense, so Savard gets the spot. If Tampa really values Coleman higher than both Palat and Killorn, then they could move both and keep Coleman instead. Tampa's cap situation will take a little work from JBB, bit as usual, it's nowhere near as bad as fans of other teams continue to hope it is.