amazon web services – AWS ELB – How to add wildcard for path param?

I want to add a path-pattern in a listenerRule that looks something like this:

/x/*/y

The trouble is that the wildcard also matches forward slash, so it matches much more than I want.
I’ve also tried to use ? as a workaround, but there is an undocumented limit of 5 wildcards, so that won’t work either. Are there any other workarounds?