Firstly, when you settled the matter with him, you should have taken back all the previous blank cheques given to him. Only on this condition, you should have settled the matter. And, if he had said that he had already destroyed the earlier cheques, then that fact should have been specifically recorded in the MOU which should have been signed by both parties, recording that there was no cheque outstanding with him (or that there was no other cheque outstanding with him barring the specified cheques).
Secondly, you have said that he sent a legal notice to you for bouncing of a cheque showing outstanding balance of Rs. 129482, against which you have now given him 5 cheques. So, if there are no further transactions between the two of you, then this outstanding balance cannot exceed the above amount (except for interest, if any).
Since a cheque bounce case can be made out only if the cheque was issued for discharge of any debt or liability, and since there is no further outstanding balance, if at all any new case is filed against you, you can take the defence of there being no debt or liability.
Note: With regard to the last part of your question, let me tell you that there is no charge for asking publicly open questions at Tilak Marg Forum. It is absolutely free.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.