I believe it will not accept name. If you would like this to happen externally you could use Caliper API's Get Vendors call to grab the id from the list of vendor names. Then use that to make your deep link.
I have attempted to use the vendorId of various entries but none have been successful. Using this page (https://tecton.q2developer.com/capabilities/navigateTo/#common-platform-feature-routes) it shows "Bill Pay SSO
tecton.actions.navigateTo('billpay.billpaySso', [VENDOR_ID])" which I have tried to use with the vendorId values that come from the Get Vendors call but none of them work.