To prevent potential problem, you would give only 1 vote for each solo/team. If it's even, then fail to /ff just like on live server.
(If 4ppl- team wanna have dinner or do anything except the league, they can force to dodge and make solo player's game meaningless.)
For example, solo + team of 4.
Each member of the team has right to vote but they would have one finalized vote as a team.
If solo player voted No and all others voted Yes, then there would be 1 No and 1 Yes at the end. So fail to /ff.
In this case, in order to /ff, they would need 1 Yes from solo player and at least 3 Yes from the team of 4.
If it was duo+triple, then they would need 2 Yes from duo and 2 Yes from triple.
And if it was 3 solos and duo, either 3 yes from solos or 2 yes from solos and 2 yes from duo would be minimum required # of yes to /ff.
Sorry about bad wording.