I really don't like what I see here.
My PSR2000 must go in for a vocalizer problem. Only have it about a month. Maybe I should wait till I'm closer to the 90 day warranty expiration date to have it looked at, as the shop might have it when it runs out. Don't think a 90 day full warranty is good advertisement for a product of this nature.
I'm sorry to see you are having so much trouble getting your board repaired.