On a secure cloud storage.
Mind telling us which cloud storage you have used ?
And did you encrypt your file which contained the seed ? Or did you store it in plain text ?
What VPN server did you use ? Did you only use the VPN to connect from your university network to your homenetwork ?
Or did you route the traffic from your home network trough a VPN server ?
The certificate usually is just for the client (you) to ensure you are communicating with the correct server.
The authentication is based on WPA2-Enterprise / PEAP / MSCHAPv2 ?
If so, the certificate is just to make sure your credentials are passed to the correct RADIUS server.
If you didn't import the certificate and connect to the wrong wifi, your credentials can be read by the malicious person operating the access point.
But you should always be able to connect without the certificate (even if it is not recommended security-wise).