I am so sorry to read about this, I fully recognize our own fight. Just wondering: why did you leave Braf inhibitors? Did you get resistance?
We had very bad time as well. Sincerely for me was horror. In my opinion (edit: I am not a specialist) my sister was at high risk in the period of 28 days wash-out, but we had no choice. We wanted to go for Nivolumab, in order to have a chance for a stable response. She lives in Romania and exhausted already two new standard therapies (zelboraf and ipi). We also exhausted our financial resources, since for us no new treatment is financed by health insurance provider. Just before and in the wash-out period she was hospitalized in total 4 times for hypercalcemia (induced by tumor progress). In this period she was almost time bound to her bed home or at hospital Finally, she resisted and her blood analyses were still acceptable in the day of randomization. She entered in study and after the second infusion she began to stabilize very slowly. Her tumors are not shrinking yet but her general status improved and she can stay on her legs and even partly work.
Wash out period + the period immunologic treatment it actually works are very long periods for somebody with fast progress. From my experience with my sister these can transform in real risks. It is something to decide for yourself and I know how hard it is to do it. Please ask a lot of questions to trials investigators. Try to see what is expecting for you after this wash out. How fast will work the combination? How many people respond and how many respond fast? Also speak with your own oncologist and try to monitor more often blood analyses (at least some significant indicators) and to keep informed the doctors from your trial. From our experience I know that in the day of first infusion your blood analyses has to correspond with their requirements, otherwise you will be delayed or -who knows- even considered not eligible.
all my best wishes and warm thoughts for you