Pink inflamed patch like rash that spreads from inner thighs to outer thighs to buttocks & starting down legs. Foreskin is inflamed but no rash. Some groin pain. Itchy. No blisters, no smell, no unusual discharge. Penis looks fine. Yeast infection?

Probably tinea. Tinea is a type of fungus that commonly causes the rash like you describe, and is less likely to cause an odor than Candida, which causes most vaginal yeast infections. Try applying a small amount of over-the-counter terbinafine cream daily. You cannot "kill" the fungus, the cream "paralyzes" it, and with regular daily use, your body will shed the fungus off your skin.