Transfer individual Creative Cloud subscriptions to enterprise for uniform billing and manageability

Our organization started using an Adobe business account in 2018 to purchase/assign licenses to our users from CDW (our Adobe Cloud Services Partner) through the Adobe Admin Console. 

We have two users that have been with the organization a long time and each had purchased a Creative Cloud (all apps) license directly from Adobe before we began using the Adobe businness account in 2018. Because of this, we have two Adobe licenses that bill monthly and aren't manageable from the Adobe Adnmin Console whereas the rest of our licences bill once per year via CDW and are manageable from the Adobe Admin Console.

I would like for both of those users to be listed in the Adobe Admin Console with the rest of the users in our organization and for their existing Creative Cloud (All Apps) subscriptions to be transferred somehow to CDW so they bill at the same time and at the same frequency as the rest of our Adobe licenses.

There are a few concerns that occur to me:

1.  The users have been using Creative Cloud for at least 6 years and probably have a lot of data stored in the cloud- we need to avoid any data loss and the users' settings and preferences should remain as they have been.  I considered just shutting down the user's existing accounts and starting new ones for them via the Admin Console but was concerned that all of their data/settings would be wiped out.

2. Both of these users registered their individual Adobe ID's to their company email addresses back when they purchased the licenses.  If the users are added to my organization's enterprise account so they appear in the Admin Console, I would need/want to use their company email addresses.  Can a personal ID and business/enterprise ID both use the same email address?  If it is possible to transfer the subscriptions over to the enterprise account, the users will probably no longer need to work with their personal IDs.

Any thoughts on the best way to integrate those two users with Creative Cloud subscriptions purchased directly from Adobe with personal accounts into our organization's enterprise account so all of our Adobe licensing is billed/managed uniformly?

Thanks in advance.