There are 2 major systems operated in an organization (an ERP and another major operational application) which are handled by 2 project managers. Data flows from the operational application to ERP. A new major request comes from client end to the project manager who manages the operational application to develop a module which will require an integration to transfer data from the operational application to ERP and once data is passed, there are certain changes that will need to be modifed from ERP end in order to complete the requirement.
My question is, should both project managers be responsible / accountable for the entire project where the operational application project manager handles until the completion of data transferring from operational application to ERP and the ERP project manager has to take care of the ERP end modification? Or else, should the operational application project manager be solely responsible for the entire project? And if it's the first scenario where both project managers are responsible, should the client be informed about the project authority level or does it need to be handled internally?
Extremely sorry if the question is too long or complex