How do I deactivate a pkey through the PHP API?

The software we use LimeLM for is tied to the physical hardware setup of the user's machine, so users will often need to have the pkey deactivated/reset, so they can re-activate it to recognize the new configuration when they upgrade the memory/HD/etc.

I'm trying to build a tool through the PHP API that will allow the users to do this themselves, rather than being dependent upon calling our support line. The limelm.pkey.manualDeactivation API call seems to offer the behaviror I'm looking for, but it requires a "deactivation request file" (rather than a pkey) as the input, and I can't find any documentation on how to generate such a file through the API.

Some of the support documents refer to an ActivationRequestToFile() function, but I don't see that documented anywhere in the API docs, so I'm hitting a dead end.

Is there any way to de-activate a pkey through the PHP API, given that you already have the key and pkeyID?