Can you use Hybrid Connector for both SharePoint and Exchange on the same CE deployment?

We set up the Hybrid Connector to connect our SharePoint Online with our Customer Engagement 9.1 on-premises this summer.
Now we’re trying to set the Hybrid Connector to connect to our Exchange Online.
There seems to be a conflict in the way the instructions say to prepare the certificate. This results in only being able to use one or the other. Setting up one the right way requires breaking the other. Both require running the CertificateReconfiguration.ps1 script but they specify a different service account for each (for Exchange it’s the async account for SharePoint it’s the webapp one). The script doesn’t accept specifying more than one service account. Do I need to use two different certs? Has anyone done this? Help!