^I'm in the same boat with him. Moved here in March of last year. Jumped through Ohio hoops in the past but glad to be rid of them... though I do go back there every couple of weeks to visit family and friends.
The Ohio Attorney General puts out a Concealed Carry Guidelines book. I just perused the pages and didn't see anything specifically related to carry by visitors Under 21 but it says it is legal for visitors to carry on their home state's license while temporarily in Ohio. Right after that it says you must follow Ohio laws while in Ohio. I honestly don't know the rules specifically regarding carry by Under 21 but I know Ohio doesn't issue permits to people under 21 so you're on that slippery slope of "nobody really knows." Personally, I'd carry. If they raise a stink, ask them why they'll honor your gay marriage but not your carry license. Take it to SCOTUS. Win.
...then we can stop asking for permission to exercise our rights.
Also, if you do head over to OFCC or BFA (Ohio's much lamer forms of INGO) be sure to call it a permit instead of a license. They love that!
Yeah! Honestly, I wish I could give him a good answer. Of all the things we discussed or argued about on those boards, this didn't come up to my recollection. I wouldn't want to be the test case.... but someone out there, perhaps as yet unborn, will be.
Chris