I'm definitely not taking sides in any squabbles here but I think that APG's reference to 'jock itch' might possibly be hitting the nail right on the head.
I've had plenty of soreness around those areas over the years through jock itch, which is basically the same type of fungal infection as causes both athlete's foot and ringworm. So using an anti-fungal cream might well do the trick. [Unfortunately pharmacists are no longer permitted to sell Canesten (= 1% clotrimazole cream) to people over 60, as it's not licensed for sale to that age group. So, if it is jock itch, you might need to ask your GP to prescribe something else, Allen].
PS: Despite the name, jock itch doesn't always cause a lot of itching. Sometimes it's just damned sore down there!