Doesn't make sense for Sharks to make any side deals. Gambrell isn't anything special, therefore paying to protect him is just harming the organization.
If there is a side deal for the Sharks to make it would be to off load one of their big contracts.
I personally wouldn't pay to move Burns as most suggest. If I'm Wilson I see what I can do with Kane first. He has had a great year and is a ideal player for playoff hockey.

We developed Gambrell & I don't want to lose him or Balcers, I'd rather give a 6th & Simek & either Donato or Leonard. Cs aren't easy to come by.

If they really want to keep Gambrell then they will just protect him instead of Donato. Protect Couture, Kane, Hertl, Meier, Labanc, Balcers, Gambrell.

You can just protect Gambrell over Donato.

I had read that we had to expose 2 Fs, with term/experience for Seattle, if not Gambrell & Balcers, do Donato & who? would qualify?

We need two forwards exposed who are signed through the end of 2021-22. So in this scenario, if you’re fine with losing Donato, you can just re-sign him before the ED and then resign Sorensen for a year as well. That should cover it. If not we can always trade for some scrub like Highmore from Vancouver who will be cheap and fulfills the expansion requirements.