IMO, unless I'm very wrong regarding the length of your growing season down south in MO, rye isn't going to do much for quail if you're going to rip it up in the spring for beans. In fact I can't think of anything that would work this late into the season. Perhaps a fast millet or buckwheat if you have at least 60-75 days frost free yet with sufficient moisture.Quail/wildlife only.
x2. I'm not sure if it's specifically the GMO varieties, but I think so. That said, I wouldn't couldn't on RR soybeans providing much, if any value for birds.... as the is some evidence that beans are undigestable to some degree by quail, although they readily eat them.