I have posted this in Technet 2 days ago and didn't get a response so I'm posting here as well.
We are running version 1810.
I have a problem with updating during task sequence. As far as I understand, SCCM should manage both certificates for third party updates and the policy to allow third party updates. But this isn't the case for OSD... I found several forums stating to add the registry for the policy and add the WSUS certificate manually but that sounds weird considering SCCM adds the certificate and sets the policy on it's own once the task sequence is done.