@ximo thank you! His voting package has not come yet (to Canada) but my wife signed for mine when it came while I was at work on Monday so that part should be ok.
I can probably courier the package to him in France. Rather than him sending the completed voting package to Toronto he might be able to walk into the Consulate in Toulouse and hand the package in there and they would forward it to Valencia? Not sure.
I think we might just get him to tell us how he would like to vote and do it for him.
@chris Hi, the documentation states that the person must either go to the consulate where they are registered or send the vote by mail. I don't think they'll accept it in any other place.
Anyway I just checked mine and the certificates are 2 printed pages. You could try to do a high quality scan of everything and send them electronically to him.