QMHSNDPM API (Sending an Escape Message)

I can't find exactly what I'm looking for in the archives and I'm done
with trial and error so here's the question. I am writing a message
handling service program using QMHSNDPM. What I want to happen is to
collapse the call stack back to the last PEP. I can't seem to get the
parameters right to accomplish this. All the RPG's run out of the
default activation group so *CTLBDY doesn't seem to work, *PGMBDY
doesn't work because it's a service program I guess. Anyway I've tried
just about everything with the parameters. So my next step is going to
be to use the API to get the call stack info so I can use that to find
the last PEP, but I thought surely there must be a way and I'm just
missing something.

Thanks for the help.
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