Just list all senders you want to allow sender login mismatch in variable "ALLOWED_LOGIN_MISMATCH_SENDERS", and place it in iRedAPD config file. For example:
# file: /opt/iredapd/settings.py
ALLOWED_LOGIN_MISMATCH_SENDERS = ['myuser@domain.ltd', 'second@domain.ltd', 'third@domain.ltd']Restarting iRedAPD is recommended.