EDIT: Apparently this didn't resolve the issue.. It seemed to for awhile, but I am receiving the errors again. Please disregards the "solution" below.
After editing bin/dbx2/health.py to log the actual exception rather than "The user [user] is not allowed to use the health logger." I was able to see the following:
11/13/2015 10:27:33 [WARNING] [health.py] [HTTP 404] https://127.0.0.1:8089/servicesNS/myUsername/splunk_app_db_connect/db_connect/health/myUsername; [{'type': 'ERROR', 'code': None, 'text': "In handler 'health': Could not find object id=myUsername"}]
Navigating to the parent of this URL showed an 'admin' object, and a 'nobody' object. Doing some digging turned up healthlog.conf inside the default directory. Adding my username as a stanza (or * if you'd like everyone to have permission) to healthlog.conf inside the local directory stopped the error messages, and has seemed to resolve the issue.
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