Linking YouTube channel with a custom URL

Hi! I’m trying to link my YouTube channel to Waypoint, but it says the link must begin with either “channel/” or “user/”. The problem is, both of these types of URLs are outdated and all custom links created since the change start with just “c/”. Would it be possible to fix/update this?

Same here. I can’t even link my custom URL since my YouTube channel is merged with Google+ which left with /c instead of “/channel” or “/user”.