We could absolutely acquire and sign Dobson for that kind of money without getting rid of major salary.
We have $5M of cap space plus we will get $6.5M in LTIR relief from Krug. That is with 14 forwards (including Dvorsky), 7 D, and 1 goalie on the roster and it assumes $2.1M in bonus overages that Puckpedia has reported we will be taking. If we traded Dobson for pure futures, signed him at $10M AAV, and sent down Kessell (our cheapest D man) to fit him on the roster, that would leave us with $2.3M in cap space with 22 guys on the roster.
That might not be enough for Hofer, but I don't think he is going to get $3.5M. If he does it is because we are buying more term than we need to. There were only 26 goalies who made $3.5M this year and there are 30 guys under contract for $3.5M for 2025/26. I'm guessing he comes in under $3M AAV on a 2 year deal.
Sending back Joseph or Leddy would create the space to give Hofer his extension and to be able to go after a center in the $2-$3M range. There are a hell of a lot of options to cut enough salary than sending a big contract to the Isles. Leddy, Joseph, and Texier are all very much expendable pieces going into next season and combine for $9M against the cap. Moving some/all of them frees up more than enough room for Dobson @ $10M plus a non-budget middle 6 C.
You'll have to see my other post about puckpedia not being able to count.