I have lost 3 more birds in the last 2 weeks. None of the necropsies show mareks, though they've all but 1 shown the wobbly walking, stepping on their own toes, etc. and the wasting. 2 teenagers and also one older hen that had been vaccinated. She, however showed no symptoms at all, and her necropsy reached no conclusion. How is that possible?
And now another teenager is starting the bad walking. And is thin. I believe this is mareks as I can find nothing else that fits. 4 in two weeks! I'm exhausted and sick.
Will I lose my whole flock? Is it possible that any will survive? I've tried everything on this thread to no avail. I guess I have to mentally prepare for the worst. Does anyone have any survivors?

It does slow down. In the past I lost 1 every few months , adults, to wasting. Most were less than 8 months old.
Some will survive. I have survivors. Most of my established flock survived it for going on 4 years. I still have about 10 of my oldest flock members. Marek's picks and chooses and sometimes there's no rhyme or reason. Even the symptoms are all over the board. Not walking and wasting are 2 biggies on symptoms.
You have to just get thru it. And know that from now on, any new chicks will be vaccinated. I also have some chickens who are from my eggs and hatched by my silkie and not vaccinated because they should be resistant. Time will tell.