Not much to go on with respect to tailoring design suggestions to the business needs, but we should be able to answer your basic question
Would this work better if we had it in service specific databases and then used a main database for day to day entry?
Definitely not. With all due respect, why would it be easier to maintain data integrity when spread out over several databases when you couldn't do it in one before? If there were threads in a forum about that issue and it wasn't resolved that would be one thing, but I have no way of knowing that. You don't break up a business process into multiple databases for the reason you seem to be suggesting.
Perhaps what you need is design suggestions to accomplish what you didn't before. To do that effectively, a lot more information would need to be revealed regarding the nature of the business and the processes that the db needs to handle to support that. Then there is a lot of basic knowledge we could suggest that you might or might not already possess.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.