I run 2 nodes, to be honest. Specifically:
Ok, that's an even better set up.

Do you also use Samourai on the go while pointed at your Dojo? Or do you just use Dojo for Sentinel?
In the past when I ran Sparrow Wallet from the command line, or at all really, I had issues getting it to connect to anything. There was no firewall running. With a Bitcoin node, the connection would not get established, and the same thing happened with public Electrum servers but that must have a more obscure reason.
Did you check the logs to find out what was going on?
That's pretty much the opposite of my experience. I was pretty taken aback when I first installed Sparrow at just how easy it was to connect to my own node on the same device. Literally one click on the button which says "Bitcoin Core" in Sparrow and it was done. It's a little bit more involve to connect it to your Electrum server or a node/server on a different machine, but I've still gone through those processes several times with different machines and OSs without ever having too much trouble.