Hello @apouriet ,
As you know, SAML works by exchanging user information, and other relevant attributes between the identity and service provider.
In order to access the SAML Attributes for Display Name for a given user so you can provided it to Zoom (Service provider); your identity provider (DUO) will need to access to this data in order to "release" the attribute to Zoom so you can then query the value from within the Zoom Admin interface
You will need to check to see what attributes are being made available to DUO via your organizations mapping of LDAP or Active Directory to SAML values.
An Example:
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displayName =
SAML Name: urn:oid:2.16.840.1.113730.3.1.241
LDAP or AD source attribute: Displayname
Example: Veruca Salt
I also attached a diagram I created to help illustrate the process/relationships.
Hope this helps!