Two related issues:

1. A value with outer parenthesis will quietly fail (only log message)

(|(memberof=cn=india,ou=groups,dc=acmecorp,dc=com)(memberof=cn=unitedstates,ou=groups,dc=acmecorp,dc=com))

because code will insert this into full filter like

(&(%s)(|(uid=vermont)(mail=vermont)))

The extra parens cause query error; the code should check if filter is already surrounded.

Additionally, if the outer parens are left off then the value inserted into config.yaml will not parse successfully. When saving to config.yaml, value should be surrounded by quotes.
The config app is exporting this properly quoted.