For some products it's possible add Product Keys through Data Analytics - Discovery Services. But in general LANDESK won't tell you the difference between officially installed software or self-installed, possibly cracked software.
You could use the assign disposition status to provide entitlement to named users using LDAP groups as alternative to see who should have the software according to your rules and who shouldn't.
For a little additional perspective on this point.
The reason why we don't collect product keys isn't that it'd be difficult to do.
If you're so inclined, you can add it as custom data by running the relevant binaries & capturing their output into custom data.
The problem is that *SOME* vendors are OK with it -- and usually only *SOME* of the time (Microsoft itself is inconsistent across the board, if I'm not mistaken). So for instance "it may be OK" to collect a product key for a stand-alone install of Visio, but it's not (legally) OK to do so with a full Office install. That's just a hypothetical example to explain the point.
Since there's additional complication that this can change from country to country (joy), and - vendor to vendor, never mind product to product from the same vendor, the general approach we've decided to take is to not collect them at all, so as not to get our customers / ourselves into possible legal problems "by default".
As mentioned above - if you're after a certain product key for a certain product - you can use Custom Data and/or Custom Vulnerabilities from patch manager to achieve this sort of thing relatively easily. That may help you answer your question about "who has legitimate & who has illegitimate versions of software Y" that you care about.
Though I'd argue, if you have to ask that question, there's far too much "local admin" access being handed out to users in the first place (may not be your call, but it's something I generally have to fight with as well. FAR too many companies are FAR too trigger happy in handing out local admin where it should be the exception rather than the rule).
Hope that helps with a little bit of insight & provides ideas on how to solve your particular problem .