Ten years old is far too young & when I was an elder I would have never have allowed any child of that age to be baptised , regardless of how pushy the parents were & how "mature" (at 10 years old?) the child was.
Regarding the sign language assembly , having given talks at sign language meetings before , I have to admit that it certainly is impressive on a certain level. This is a sector of society that is ignored by many , and the JWs are filling the vaccuum to an extent.