Integrating plugin with our IDP

Hi,

I am in need of help as I am trying to use the wp-saml-auth plugin with a WPengine hosted site. It is not a transferrable site nor a multisite. We have provided the information to the form that is being requested and read the documentation but still seem to get to the point where our IDP is requesting the user to authenticate themselves and passes that stage. What does not seem to happen from that point is that the user is not them passed back successfully to the wp-admin area, or is presented with the login form to login from. We are only using this to protect the wp-admin area for users that fall into an administrator role according to our IDP. We are now just trying get an authentication on any role at present.
The phenomena we see is either that we see a bouncing effect between the WP site and our IDP where the SAML details for my user were correctly showing in SAML trace but the request to authenticate was being returned to the IDP from the WP site, or that we get to the IDP from the WP and are just shown the metadata from the IDP and no further redirectin from the IDP to WP occurs.
I am not, I confess, our companies expert on our IDP but am trying to drive this along as we are about to migrate all of our on premise WP sites to the cloud hosted service.
The WPengine provider does not have simplesamlphp package installed on the docker machine we have with them.
Is there anything you can do for us to get this working, even if it is some short term consultancy.

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