Silver only books to 32 seats on the Saab, so you automatically have 2 open seats in the back. Not sure if you can jumpseat on us internayional though, i would need to look that one up to be sure. The few times I've been out there, we could have easily taken a non-rev to MHH. Good thing about Silver is that there are now 3 options for getting out there, so if you get creative, you should be fine.

As far as not going to EYW on Eagle, if you are willing to avoid FLL and TPA, take the Saab through RSW. Loads on that segment generally are better for non-revs than the other two. FLL and TPA get very restricted coming out of EYW, but are generally good getting in most days.