Tenant wish to create Promissory note on Late Unpaid Rent

[James Hsia]

Tenant has extenuating circumstance and unable to pay rent for next 2 months (I already served him with 3 day pay or quit).  He suggested a promissory note which forfeits his security deposit as a short term bridge payment to cover for late rent as well as promise to pay 2 months rent. Note also stipulates if payment isn't paid by next 2 months, tenants will agree to vacate home before Oct 1, 2018. 

Has anyone had any experience with a situation like this? The promissory note sounds rather one sided, since he could just bail on 2 months rent and when it comes to the agreed day to vacate they will just not move out.