As a former owner of an Odyssey, I can almost guarentee you it is the rotors. What is commonly referred to as “warped rotors” is almost certainly “uneven pad transfer.” That oocurs when brake pads exceed their design limit for temps and pad material “melts” onto the rotors. Sometimes you can even see it on the fronts, which do by far the most work. It can look like a smear of peanut butter, strange as that sounds. Honda discs can not generally be turned as they are not made with hardly any extra material. I have had good luck with Centric 120 series rotors. Also, go ahead and replace the pads at the same time, then torque the lugs with a torque wrench.