Microsoft SPLA Licensing - Migration Question - Previous IT setup Incorrectly

Hey Guys

We recently took on board a new customer. They have quite a large network (30 workstations and 7x servers running different services: exchange, SQL, Sharepoint etc etc).

The previous IT company set up the network using Microsoft SPLA licenses and the customer was paying a monthly fee for that.
Under the Microsoft licensing agreement. SPLA must be installed on equipment leased by the company providing the SPLA licenses.

However, what we've found is the equipment is not under lease and the equipment is owned by the customer.

We've emailed the Microsoft SPLA department and also liaised with the SPLA resellers in our country. Most of them say that the customer will need to lease new equipment and SPLA through us and rebuild the network.
However, one SPLA supplier said we can buy the equipment for $1 and lease it back to the customer and then apply new SPLA licenses using a SPLA license key changer, which we've seen exists on some MS forums.

We're looking for the best way to help the customer and if possible keep the existing install environment to limit downtime for the customer.
 
How can we help the customer in this difficult situation?