Notebook Hardware and Upgrade Questions

Hi Community,
last week I've started at a client computer Windows Updates and after via HP Support Assistant Firmware and Driver Updates.
A firmware update for the connected HP Thunderbolt Dock 120W G4 docking station was also displayed. Unfortunately, customers and I often have problems with the HP Thunderbolt docking stations, so I decided to carry out this firmware update.

After a while I realized that the firmware update for the docking station was taking too long, but I waited until the support assistant also noticed this and canceled this update and then continued with the next driver update.
After the restart, there was no longer any image on the two connected monitors, and after opening the notebook display it became clear that the docking station no longer had any function, the notebook no longer had LAN access, the external mouse and keyboard no longer worked and the power supply no longer worked was gone.
Restarting the docking station by unplugging the power supply for longer than 5 seconds and other tips didn't help.
The docking station is around 400 days old, a call to HP revealed that the device is out of warranty and nothing is possible here.
But an error that results from a firmware update gone wrong can't be seriously dismissed by HP.
What can I do, the customer has no understanding of HP's behavior here, as the docking station was still working before - apart from the general HP Thunderbolt docking station problems.

Alex