بسم الله الرحمن الرحيم
(1) Since Hajj was fardh on him; hence if he has not performed his fardh hajj earlier and he submitted his form for fardh hajj this year then it is necessary for his heirs to send anyone for Hajj-e-Badal on his behalf. They should send any pious person who has already performed his fardh hajj.
(2) It is not necessary to fulfil the wish of your father regarding the grave as per the Shariah. Hence his burial in the ancestral graveyard was alright. You did a good job as you asked your relatives not to wait you. It is the ruling of Shariah.
Allah knows Best!
Darul Uloom Deoband