If proxmox is connected with ethernet you have nothing to do with wifi. With your setup you should reach any address in the network.
Check tha you can ping an endpoint
- from the proxmox host
- from the vm
Post your network settings of your proxmox server and the endpoint. Check the netmask (/24).
ip a # on proxmox
Wifi-connected dietpi
I used a proxmox container as roon server but switched to an even cooler setup with roon as container within Truenas Scale that is running fine (since a few days). But that’s another exercise.