Use following filter hooks and unset $args['mgs_type'] and add $args['mgs_type_in'] = [ 'message', 'announcement' ]
fep_message_count_query_args
fep_message_query_args
fep_filter_get_message_with_replies
(Untested)
Use following filter hooks and unset $args['mgs_type'] and add $args['mgs_type_in'] = [ 'message', 'announcement' ]
fep_message_count_query_args
fep_message_query_args
fep_filter_get_message_with_replies
(Untested)