Trap and “dispose of properly”.
Once some coons have their sights on your place, you are lost, they don’t discourage from their fun and games.
We had them tear the door to the tack room to get in there, then when they could not the second, stronger door, they made a hole in the wall by it.
Another group of those made a hole in the roof to get in there.
Once we had a whole herd partying on the house roof most nights, ended up trapping 11 of them that time.
They could have caused a fire, they were shimmying up the conduit and overhead wires to get up there.
A wonder none of them was eletrocuted.
When we were one winter tearing down our old race horse training barn the termites had been eating clear to the rafters, we dug out the biggest, fattest coon you ever saw in your life.
He half woke up and wobbled into the woods, grumbling about such rude neighbors disturbing his sleep.
Somehow he got into the insulation on the ceiling in the bunk room and was happily hybernating there.
We have plenty more coon stories, none of them good ones for us, the coons and the serious destruction they cause.
We have our current feed room in the house, in a spare room behind the garage, not in our barn.
We don’t want to attract any wildlife in there we can keep out.
In our new barn, the feedroom there is a designated critter proof room.
You can try moving your grain somewhere safe, lesson learned and hope that one coon will get discouraged and move on and that would be lucky for you and the coon.
I am surprised you didn’t mention he trashed the feed room.
Ours have always left impressive destruction behind them, the “no unturned bucket is a good bucket” kind, shelves cleaned out, everything on the floor and thoroughly shredded into.
Depending on where you are, you could contact your game warden.
Here you do that thru the sheriff’s office.
He will tell you what all is best for wildlife in your area.
They have seen it all and can advise what the laws are in your area and who can help you if you need to trap and take care of any wildlife.