Is it permissible to pay the expiation of an oath to a charitable party as it feeds the poor and needy such as Tkiyet Um Ali?

All perfect praise be to Allah, The Lord of The Worlds, and May His Peace and Blessings be upon our Prophet Muhammad and upon all of his family and companions.

There is no harm on authorizing someone to handle the expiation of another to the poor and needy, since Shafiee's jurists stated that authorizing someone for the purpose of distributing Zakah, expiation and vow is permissible as stated in [Mughni Al-Muhtajj, vol.3 pp.237]. At last, the intention of the person who intends to authorize someone else suffices in this regard. And Allah Knows Best.

Should one obey his mother even if she was wrong?

Obeying one`s mother is mandatory in matters that are beneficial to her and as long as she drive her children to commit sin.

Is it permissible for a Muslim physician to specialize in GYNECOLOGY OBSTETRICS, and what is the ruling on working as such?

Some fields of knowledge are an individual duty while others are a collective one, and specializing in GYNECOLOGY OBSTETRICS is a collective duty. However, if there were female physicians to treat women, then there is no need for a male GYNECOLOGY OBSTETRICS specialist to look at women`s Awrahs (private parts) except in necessary situations since the jurisprudential maxim says:” Necessity must only be assessed and answered proportionately.”

Is it incumbent on a wife whose husband hasn`t gone to bed with her(for sexual intercourse) for many years to observe `Iddah(waiting period) upon his death?

Upon the death of the husband, a wife is obliged to observe the `Iddah even if he hadn`t slept with her because she inherits him.