I don't know vine maples, have never owned one. I do have other maples.
I would not worry about the first set of leaves going south. As long as you have a "good set" on the trees, if the oldest leaves drop its not a big deal. But again, I have no vine maple experience. Possibly your vine maples are still adding to their roots systems, and the new growth out-grew the root system, so they drop a few older leaves to keep in balance. If they are the ones doing the balancing, it will work out fine. I would do nothing but maybe remove the wilted leaves.
4 success for 4 attempts at fall collecting for vine maples suggests that its not a bad time to collect them them. Your winter storage worked for them. You should feel free to collect more, and other deciduous too. Autumn collecting of deciduous has the advantage you can see leaves, and identify the species before you collect.