I wouldn't add any moisture to something which was to become long-term storage; you can always rinse and soak them when you open them up after a few years - estimates were generally in the 5-7 year range before they wouldn't cook properly. Moisture just isn't your friend re: long-term storage, and the beans are already dehydrated.
I've been told that beans in particular are hard to cook up after a few years. We tried cooking up some pinto beans which we'd vacuum-packed in mylar back in 2011 and discovered that was true. I think we cooked those beans for over a day and they never softened up! Although they were edible ....
So we tried a suggestion from our group - using a pressure cooker. This worked great! The electric one - Instant Pot Duo Plus 60 - has a 45-minute pressure soak cycle or something, after which it cooked the beans up real nicely in less than a couple hours, IIRC. (It's been a while)
The other suggestions which seemed meritorious were to either grind the uncooked beans into powder and add that to dishes as a thickener, and I'm told that the powder can also be used as flour also. I suppose that could become like refried beans as well. We've not tried this personally yet but we probably should soon.