Didn't the consultant document what he did? Anyway, I assume you have a prove of purchase for the licenses? With this you may contact VMware and ask them to check to whom the licenses are currently registered and/or to move them to an existing My VMware account for your company.
Regarding free upgrades: If - at the time vSphere 5 was released - your subscription was still active, you should be able to upgrade free of charge. However, you can only do this in the My VMware account to which the licenses are registered.
André