they can do that
when I first wrote hedgehog, it could do asynchronous payments, but only if you had a direct channel with someone
then I implemented a protocol that allows hedgehog nodes to "route" asynchronous payments over a series of hedgehog channels, which has a lot of huge benefits
recently, however, I realized that the protocol I implemented only allows users to have one routed payment "pending" at a time, and they can't really use their wallet anymore until it resolves
I think I've thought of a way to fix that but I am not sure and I haven't started implementing it yet either