FYI: Splitting of fees with the cohost and directing the cleaning fee to the cohost have been removed as options as of Aug 1, 2018. Here is the reply from support on my inquiry.
We recently announced that we're removing the co-host split payout feature as of August 1. We understand this may impact how some of you do business, so we want to give you background on why this change was made, along with some suggestions for how you can get paid now.
When we originally added the split payout feature, the co-hosting program was much smaller. But as the community grew, we realized the feature was no longer addressing all the needs of hosts and co-hosts or meeting our internal reliability standards. We know this feature is important to certain co-hosts and will keep you posted as we work on a new one and continue to improve the co-hosting program.
For now, here are some other payment options to consider with your host:
Hosts can split guest payment with you in their account settings. They will need your permission and account details, as well as the agreed payout percentage.
Explore alternate payment methods outside of Airbnb, such as secure online payment apps, bank transfers, checks, or cash.
We sincerely apologize for any challenges this change may introduce and hope this gives you some context and takeaways. Thank you for co-hosting—and being a part of the global host community.
—Lucas
Suzanne Darnell, Mind Matters Wellness