You could try using ssh reverse proxy and proxy the port to the vps.
Another way is to setup wireguard on the vps, connect the powerfull machine to it and keep it always connected there. ( This isn't really a good options since then all traffic is moved thrkught the vps )
There is also grok I think that's the name.
In general I think ssh reverse port proxy would be a decent way and then you can use a reverse proxy on the vps like nginx or caddy ( you need one that works on the host network )