EEA Family Permit - original passport or certified copy?

Hi all, can anyone help?

Regarding application for EEA Family Permit for my wife, the application page on gov.co.uk (https://www.gov.uk/family-permit/surinder-singh) states:

"You must provide your family member’s valid passport (or a certified copy if you can’t provide the original)"

Ideally I want to keep my passport due to some issues during the time the Family Permit application is submitted.

I know they are getting more and more strict with original documents.

Does anyone know if there are currently any problems with supplying a copy of my passport certified by a Notary Public here in Germany? Will we have any problems with the ECO if I submit a certified copy?

Many thanks.

Just to confirm, we are applying via Surinder Singh route. I am British and the EEA FP is for my wife.