Problem setting it up

Hello,
for the company we already bought  license from you. 
For temporary private use i had a RPi Zero lying around with VH installed on them so that i was able to get a RX/TX wherever i needed it. (i set this up two or 3 Years ago, cant remember)

I have not used it for a while but need it now quite urgent as a fixed installed smarthome component need a important software update.

Unfortunately we have changed our Wifi setup since last use, so the RPi Zero is was able to connect to it.
As a quick fix i temporary reconfigured the Wifi setup to have the old credentials and SSID so that the RPi Zero with the VH Server could temporary get connected but i found no way to change the Wifi Setup then. 8VH client does not offer a configuration option). So the last Idea i had was to restored the Wifi config back to its actual state and simply reinstalled VH on the SD card of the RPi.
Now i again stuck as i do not own a Computer with Wifi to do the Wifi Setup again, all my Servers and Workstions ... are connected by LAN (they have to Wifi Hardware built in) , Wifi is only used for Phones and tablets and the only 10 years old Laptop runs Win7 where i can't get the VH Client to start.

Any Ideas how to go further ?

Many Thanks,
Walter