I'm not sure if this is the right place to post this:
We are seeking a Moodle partner that can collaborate with us develop a multi-tenancy capability for our Moodle version 3.3, that we can share with the Moodle community. We are looking to achieve the multi-tenancy result through any combination of theming, custom role configuration, plugins ect. We are aware of a number of Moodle forks such as IOMAD that provide the multi-tenancy functionality, but we do not wish to modify the Moodle core at this time. A key requirement for the multi-tenancy is to be able to implement a Manager Role that can show and hide users from other site Managers depending upon the group that they belong to. The purpose of the Custom Role capability is to isolate colleges from one another that share a single installation of Moodle.
In the spirit of full disclosure I have had some dealings with Iomad over the years so please read my reply in that context.
We looked long and hard at ways of achieving multi tenancy without core changes. We concluded it could not be done and elected to make the minimum changes possible.
There is certainly nothing in the capabilities to help you.
Of course, you may come up with a solution and I’ll be more than happy to admit I was wrong. Beware of “reinventing the wheel” however. We’d certainly be more than happy to help you make Iomad meet your more general needs.