My advice about staying out of the current contractual relationship with the other billing company stands no matter what.. stay completely out of it and instead all information should come from the provider directly.
Often we have providers who will ask us to "work with" the previous service to get any information we need. Linda is right. Stay out of that relationship. That's like the new wife asking the old wife for her husband's favorite recipes.
We've had situations similar to what you are describing below. We do have providers who have EHR but do not utilize the billing portion and we do the billing from our system. That is how they want it done. They have been using us for 20 years and they obtained the EHR a few years ago. When they first started they didn't even have a computer. We now have access to their EHR and we can obtain the billing information. It isn't compatible with our system but we are able to print out the billing so that we have all information needed. This save the provider's office time, and it's in a great format for us. It's the same as if they gave us paper data, but it's all typed up.
Their EHR system pushed them hard to use the billing portion and to let them handle the billing for a MUCH lower fee than we charge. But our provider knew that the billing was handled overseas, and that they don't really "handle" the billing. They basically submit the claims and then provide reports to the provider about which claims the provider's office needs to take care of.
When we have a provider who is leaving a previous outside billing service who does the billing from the BS's software we advise them that they should request a copy of the current AR (total AR not just over 30 days). We also advise them to check over their contract to see what the termination terms are. Usually the previous biller is responsible for working any AR that was billed by them but unfortunately there are all too many that don't. Let's face it, if there wasn't an issue the provider wouldn't be switching. It's not always the billing service's fault. When we have an account leave us we clean up any outstanding claims submitted by us and provide a report of any claims that we were not able to clear up and why. I have not seen that in any cases where we took over from another billing service.
There are a lot of good billing services out there but there are an equal number of bad ones. We have a local one that we know for fact they do not work aging reports, they do not send regular patient statements, and they do not handle denials. We receive 2 - 3 calls a year from clients of them that inquire about our service. We advise any potential client that if they use an outside service that utilizes their own software system they should at lease receive regular aging reports showing what money is out and how long. The BS should be able to explain anything on that report.