I'm sorry for the information but there is no ALE support for the vendor contact persons.
This feature has not been developped and there is no plan to develop it for the next releases.
The only solution I can see is a consulting project.
SAP can help for you this.
If you are interested in such activity, I would encourage you to open a customer message in SAP marketplace under component LO-MD-BP-VM and ask that the message gets forwarded to development support. You may also add my name too in order to speed up processing.
Sorry for that information