SP cannot handle multiple IdP

[Qian, Yi]

Hello, 

University of Kansas recently signed touchnet for student services,
management just found out, they can only support single IdP. 

The problem is university has different entities each has own IdP, each
IdP has its own backend LDAP connections and university does not have a
centralized source.

Could someone recommend a way to handle this SP? I am using Spring
extensively at work, it is fine to write code if requires.

Thanks
Yi