Taking Tabarruk from the Awliya and Buzurgs

Q: A sheikh of tasawwuf told his murid, who was going for four months to read salaah at a certain spot in Nizamuddeen markaz where Ml Ilyaas (Rahmatullahi Alayh) used to read tahajjud salaah, is this not bidat? Is such a action established in deen? If there is such a thing as taking barkat, will it not be restricted to Nabi (Sallallahu Alayhi Wasallam)? Please answer in detail with relevant proofs from Quraan and Hadith.

Hajj with Haraam money

Q: Is a hajj that is performed by someone who's money is 100% haraam from selling drugs accepted, the person is a drug dealer. When the person is on Arafat is all his sins also forgiven when returning as a Hajji. Please give a detial explanation & what is the punishment.

Fasting on Mondays

Q: An Aalim says: Traditional Eid-e-Milad-Un-nabi is Bid'ah. It is not Islamically right. But, it is true that Rasulullah (Sallallahu Alayhi Wasallam) himself celebrates the days Modays keeping Fast since it was his birth day, day of Hijrat, day of getting Nabuwat etc. I would like to know, if it is correct and if so, can we keep fast on Mondays like our prophet (Sallallahu Alayhi Wasallam)?