I’m afraid you will need to recreate your ROOT file and define your tree master branches in a different way. For all of them, either modify the “branchname” adding a “.” (dot) character in the end or set the “splitlevel = 0”.
If you do not want to (or cannot) regenerate your tree, I guess (and @pcanal would need to confirm it) the MakeProxy, the TTreeReader (plus the new MakeSelector which uses it) and the RDataFrame should be able to deal with what you have now.