In order for PIC to work, the access edge must trust on both sides. The entries that exist in Skype for Business server means that it's configured to trust those providers. But, you still need to get Microsoft to trust your Skype for Business Server. For
that, you need to go through the registration process and provide them with the SIP Domain and FQDN of the Access Edge. They will configure the other end to trust your deployment and the handshake will be completed.
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