How to best patch a tear in polyester and elastane man's shorts?

My son tore his Patagonia 91% polyester 9% Elastane shorts. The tear is about an inch long but frayed. I stitched the sides of the tear together but it doesn’t look great and is a bit bunched as I had to pull a bit more fabric into the sewing as the fabric frayed a bit. Can I use an iron on patch on the polyester and elastane material? I am not sure if I will melt the fabric. I would appreciate any guidance you can give about how to repair the tear and/or whether I can use an iron-on-patch the fabric. Thank you.