I've tried to add ts.shilab.com to the SAN extension but receive an error when I run Set-CertificateExtensionwhat error you receive?
looking at your request and it contains all mentioned names:
2.5.29.17: Flags = 0, Length = 3b
Subject Alternative Name
DNS Name=ts.shilab.com
DNS Name=mail.shilab.com
DNS Name=autodiscover.shilab.com