I found it easier to create extra data fields and run a script on my managed services machines to input the last 5 of the serial into the extra data fields. Basically slgmr and ospp.vbs. I created a wrapper with goto's for the products detected on the latter. The product key stuff in labtech usually retrieves BBBBB-BBBBB-BBBBB-BBBBB-BBBBB for volume/Mak licenses. Plus, if the agent is deleted, the information remains.
I created an EDF for the OS and additional EDF's for each version of office we have deployed. 2010, 2013, 2016, etc.
I then created a dataview to pull the EDF's I created . The hard part is then taking the excel I export from that and marking up the spreadsheet vs licenses that I have. Couldn't find a way to automate that part of it.
The script is hard to perfect because of 64bit os vs 32bit or 64bit office. Also, sometimes more than one office product has been installed due to an in-place upgrade etc. But it is better than trying to audit 3000 agents!