Hopefully you make some headway with Atrius. They partner with Beth Israel when need be and I was able to get in relatively quickly (2 weeks) recently for another cancer scare.

I saw you mention trying Tufts. Spouse and I both initially went there because it was the only hospital system we could get into with any expediency, BUT they have dropped the ball so many times leaving us without care. Both of us have had appointments (spouse for a somewhat intensive procedure) made and then...nothing. We disappeared off their schedules. I've heard several others have similar experience, and several ex-staff told me it was not particularly uncommon at Tufts. Just our experiences, though.