How to Get Unspent Transaction Outputs from Node
listunspent will list all unspent outputs of addresses the wallets controls, it will not work for any arbitrary address.

You can importaddress to add any address as a watch-only address, but this may take some time as your node will need to rescan the blockchain to find all associated transactions. Also note that when you use importaddress, you will not be able to spend any funds held at that address, since your wallet will not hold the private keys for it.