1)In this case, does j2 is waived the 2-yr service obligation?
Not yet.
2)if not, j2 has to get a waiver letter, but chinese embassy never gave j2 waiver letter.
J2 has no way to get waiver independently unless J1 is dean or J2 divorce from J1. or J2 go back to china for 2 years to satisfy 2 year rule.
3)chinese embassy do not give waiver letter to j1. They say that j1 has completed 2yr service and need not the letter.
Chinese embassy is right
does h2 has to go back to complete her service? what options that she has?
the another option is : J2 and J1 divorce