Dicor makes products appropriate for either an EPDM or TPO roof. They also have a video telling how to determine which you have. Your roof is 17 years old and chalky is normal. My 2002 original roof had large areas where the pigment (white) was gone showing the black EPDM roof material. I had my roof replaced by RV-Armor so I would never have to get up there again. It is expensive but a leaking roof will quickly ruin any camper and water intrusion is the most common reason for campers turning to junk.