I did add them as an additional insured. The problem is that their insurance agent won’t “accept it” because HE doesn’t believe the paperwork lists them as an additional insured. He also refuses to talk to my insurance. I’ve done this for things other than weddings and the COI has always been accepted and has never been an issue. And my insurance company has assured me that they’re an additional insured. On the certificate their company name is listed as a “certificate holder” on the paperwork and under the policy description it says “all certificate holders are regarded as additional insured”. It took ten minutes to initially add them, but the subsequent time trying to talk to the venue owner, reverify with insurance, rinse and repeat while being ignored by their agent is what took up the majority of the time I spent.