How do we stipulate outside of court to end supervised visitation?

My ex has supervised visitation 1 hour per week with my daughter due to prior drug use. My ex’s sister is the supervisor for these visits. These visits have been going on for almost 6 months. The supervisor does not do the job of a supervisor and is not looking out for the best interest of my daughter rather the best interest of her sister. I am contemplating stipulating that it is not necessary to have the supervisor present given visitation remains at the designated located. My ex appears to be clean and I don't see any reason for her sister to continue to be involved in these visits. In addition, I thought my stipulation could include a clause stating that if I suspected drug use I could supervise the visits until we were able to go back to court for a drug test. I am just concerned I may be shooting myself in the foot by eliminating the supervisor however the other part of me would hope the court would appreciate my efforts to stipulate outside of court. My daughter who is 10 also knows she is not to go anywhere with her mom etc. She also does not desire any more visitation with her mother than what they currently have.