Am I correct in thinking BOTH borrowers or any parties with the right to rescind need to provide e consent prior to sending the CD electronically?

For example: The borrower gives consent, however the co borrower never does. I am thinking we should not send the co borrower the CD electronically......

All parties that are to receive written copies of the disclosure must consent to electronic delivery.

Thank you Dan!

How would this apply for a non borrowing spouse?

Are you in a marital property state? Is the spouse on title?
As Dan said: All parties that are to receive written copies of the disclosure must consent to electronic delivery.
Here, that means the non-borrowing spouse must consent to electronic delivery.