You can configure Horizon View for RADIUS in which case Access Point can be configured for pass-thru authentication (the default setup). In this case it will pass through RADIUS and SAML requests to Connection Server.

As you say, if you configure Access Point to require RADIUS authentication, then it will do this always, and will not pass-thru SAML.

Another option is to have one Access Point configured for RADIUS and connecting to a Connection Server configured for password. Then have another Access Point configured for pass-thru connecting to a Connection Server configured for SAML.

Mark