No that is not correct, you added /api/v1 to the URL it should match the sample provided by them.
/api/v1 is specifically for REST calls.
Though I’m not sure if they enable the WCF End points publicly for the SaaS side of things.
Since you are SaaS you’ll probably have to use the REST end point and NOT WCF
To use the REST end point you can find documentation in the Epicor Help,
also
Here