Isn't the idea to trade Brannstrom for a pick or something, and waive Joseph. Ideally Joseph clears waivers, and you get to keep him for when you have room again under the cap.
Waiving Joseph alone doesn't seem to create enough room, but trading Brannstrom on top of that should.
The rumoured offer to Pinto is 2x2. If he accepts that, then Brannstrom is money in/money out.
Waiving Joseph+Brannstrom out frees up 3.125M of cap. That would give the Senators 3.18762M of cap. That isn't enough to sign Pinto at 2.5M and bring up an extra body with their current roster as it is. Also, Joseph is likely much better than whoever the replacement body is, and he had a strong pre-season and first game.
They need to move both Kubalik and Brannstrom to sign Pinto and free up enough to somewhat improve their issue with healthy scratches. They likely won't do that. They will trade one of them and play short-handed.
I just don't see the rationale in paying to move Joseph right now because it will be easier to move him next season when the cap goes up and teams have more cap flexibility. He is also more valuable to this current lineup than Kubalik or Brannstrom. Kublaik or Brannstrom will either bring back a small asset, or take a lesser sweetener if there are no real takers as they are.
The only reason to move Joseph right now is if someone offers the Senators a great deal, like taking Joseph for a 2nd, which is what he might cost to move next off season. That, or if there is truth to the Flyers liking Boucher, and the Senators no longer value him like a 1st round pick. Although, I would be reticent to move Boucher.