We use Lenovo laptops, and I have recently found that they have a tool called Dock Manager, that among other things can update WMI with Serial Number and Firmware versions. Unfortunately much of our existing inventory of docking stations are an older model that this software doesn't support, but I've seen it work on some of our newer docking stations. If it helps, here's some info: https://download.lenovo.com/consumer/options/dock_manager_readme.txt
I'm looking at trying to make use of it anyway, and if Lansweeper can't pick up this information automatically, I'm looking at using a PowerShell script to write it to a custom registry entry that I can tell Lansweeper to read in.
Sure would be great if Lansweeper could do this automatically without me having to do so much as custom work.