I have two Entra SSO apps. The reason I need two, is that one of them is linked to AD-On Prem. This one combined my actual users. 

I want to add Entra users from another tenant. This is working in other SSO apps to auth them. They don't have on-prem AD accounts.

The main problem I have is that when the second button on the LFDSSTS page is clicked that should be linking with the second, cloud only entra app, it tries to validate the first/original Entra application. I can tell because the error references the original entra SSO application ID.

I have both Entra apps set to append the issuer with the application ID. 

I'm not sure why the second SAML SSO button on the STS page is directing the auth to the original SAML SSO app. 

Both apps have unique users assigned to them. Entra auth works for both users, internal user and external user. The SSO button on LFDSSTS just isn't referring to the correct Entra app to query for authentication.