Creative Suite and Firefly on Separate Accounts

We have a business account and an Enterprise account. All of our applications, like Creative Suite, are licensed under the Business account and we want to add the 50,000 Firefly credit Premium pack to some of our users. Apparently this is not possible on our Business Plan. 

If we purchase the Firefly licensing under the enterprise account will this work? Or will we need to move the applications over as well? We are having a hard time getting any accurate information, including an explanation of if the 50,000 credits are one time purchases per user, or if they are 50,000 credits per user per month for the 1 year term. 

Any guidance would be helpful.