بسم الله الرحمن الرحيم
(1) The members of an NGO cannot take their remuneration from the amounts which an NGO receives from the government under various schemes. As per the government rule they are working voluntarily without salary; hence it is not lawful for the NGO members to take their compensation from this amount without the permission of the government.
(2) No, it is embezzlement and haram. The amount should be spent in the same head for which it is meant.
(3) In this case if it is not against the law to take remuneration from the income of hospital etc for the members then they may take compensation in the name of management and care of the hospital, otherwise not.
Allah knows Best!
Darul Uloom Deoband