What should I do if wipes are making my baby's diaper rash worse?

Avoid wiping motion. If cleaning with baby wipes seems to make a diaper rash worse, try cleaning by dabbing with a moist/wet tissue, or by rinsing the butt with water and dabbing dry with a towel. Avoid wiping the skin, because the wiping motion may rub off the new skin cells that are forming to heal the rash area. If the diaper rash persists, a doctor should examine it.
Make your own. Occasionally the fragrence oil or preservatives in diaper wipe products will aggrivate any area of skin that has broken down. A short term fix involves soaking paper towels in baby oil & keeping in a ziploc bag. You can make these problem free wipes for transitional use and return to the others after the skin has healed. Open air drying, thin soapy water cleanup etc when possible also helps.
Wet washcloth works! Use a wet washcloth or simply put them in bathwater and swish! a lot of wipes contain alcohol or other ingredients that can make rashes worse. Adding baking soda to the water can also help neutralize any acid in diarrhea. Another secret is to make sure they are completely dry (use another diaper to fan) before putting on the diaper cream. We call it the 2 diaper method at my house!