Yes, but setting the environment variables before running setup. The following two coded env vars will set your btcpay server to automatically also run a tor hidden service. Once XMR is configured (only one wallet per server at the moment) you should be able to access the hidden service and pay without issue.
Run btcpay-setup.sh with the right parameters
Set the custom domain you chose to use
export BTCPAY_HOST="btcpay.EXAMPLE.com"
Use Bitcoin on mainnet
export NBITCOIN_NETWORK="mainnet"
Enable Bitcoin support
export BTCPAYGEN_CRYPTO1="btc"
Enable Monero support
export BTCPAYGEN_CRYPTO2="xmr"
opt-add-tor enables Tor support for the UI and Bitcoin node
export BTCPAYGEN_ADDITIONAL_FRAGMENTS="opt-save-storage-xs;opt-add-tor"