If you want to send a call from Tenor to the softphone using SIP, you will need a SIP server and proxy, however, if you only want to send a call from softphone to the tenor, then you should not need the proxy and server.
I can provide you my services to configure the tenor. I have not worked with the softphone, so I am not sure about its setup. You may want to check to see if this software needs a SIP server/proxy.
If you would like to use my services for the quintum setup, please contact me at email@example.com