That link states "As an Air Canada Top Tier member, you will be able to share your eUpgrade Credits with other travellers, known as eUpgrade Nominees, even when you are not travelling with them. Your nominees must be Aeroplan members."

which I read to be that your traveling companion needs to be on your nominee list. If you are not traveling with them you can still request an upgrade for them. Nowhere does it explicitly state that your traveling companion does not necessarily have to be on your nominated list.

To the OP

What exactly does AC need to make up for? This was a policy that was changed last year. There are advantages and disadvantages to this policy but where exactly did the AC agent do something that went against published AC policy on upgrades? Why does AC owe your traveling companion or you anything? You have chosen two nominees for your list. Unfortunately you did not deem your colleague to be important enough to give him one of those spots so why should AC?