My friend asked me to invest. I did so. He asked me to recommend others. I did. Now he has cheated all of us and disappeared. Those whom I recommended are harrasing me for money. I am in total depression and have no peace of mind. They are accusing me, some even calling me a conman. I am performing many prayers to overcome this problem. I am very, very sure I didn't cheat anyone. But I can't take the accusation. I beg ALLAH for forgiveness if I'm in the wrong. Four years have passed, but I am still in depression without peace of mind. Please advise. Do I need to pay all those I recommended? Can I go for Hajj?

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

It is a duty on your friends to be pleased with the Divine Qadaa and Qadar and to stop calling you a conman, a bad nickname. Allah says: {……nor insult one another by nicknames…….} [49:11]
Then, they have no right to ask you to repay money which the false investor stole. Since you are not responsible in this concern nor did you give their money to him. Informing them about him does not make you responsible to bear such responsibility, i.e. towards their money. Here, we state that you can perform Hajj as long as you are able to do so. The situation you mentioned has no relation with Hajj.
Allah knows best.