Hi Justin!
> I do not want to verify ANY mail that comes from services.cam.org. If
> it comes from this host, then just pass it through and I will spam
> filter after the fact.
OK, what you need then is an unconditional accept instead of a
conditional deny. Place the following ACL entry *before* any ACL
entry that has "verify = sender..." in it:
accept hosts = 198.73.180.252
The best place in the default Exim config for this is right after the
"accept local_parts = postmaster" entry.
Andy