We are having exactly the same issue as you. We're using DigiCert certs (SAN certificate). All other end-point clients work fine, other than the WyseP25's (firmware version 4.1.X, View 5.2). We have uploaded both the DigiCert intermediate root CA and the SAN cert (both in PEM format). The error we're still receiving is Failed to connect. The server provided a certificate that is invalid. See below for details: The supplied certificate is not rooted in the device's local certificate store.
The certs (both) are 100% in the device local certificate store (via the PCoIP Management Console). I've attached a screen shot of the certificate store and log file. Any help is appreciated.