I would legitimately ask Sid. He's that important to your franchise.
Have a conversation with him and be like: look, we're stuck between a rock and a hard place. You want to stay forever, we want you to stay forever. We want to ice as competitive a team as possible, but right now it just doesn't look like that's in the cards. For the benefit of the franchise you have sweat and bled for, we're going to tear it down to the studs around him (minus malkin and letang unless they wanna go) unless you tell us you absolutely do not want that, in which case we'll keep treading water.
I think he'd give you his blessing to do it, in all honesty. I have a lot of beef with Sid stans, but gave up criticizing him as a player or leader a very long time ago.
Pens were a real tire fire his first year, poetic if his time concludes there the same way.