The one reason I think that this feud was destined to fail at the start is because of when they chose to debut the new kid. If you are going to bring someone new in an immediately have them feud with The Undertaker then late December and January terrible picks unless it's going to be a short feud due to the Road to WrestleMania. With that being said it is tough to conclude that Hade would never work in a feud this close to WrestleMania.
Following his departure from the WWE his career would continue in his home country, but would fall away from the wrestling business. I think that at a different part of the year maybe when they started the Khali feud like post WrestleMania. Maybe if they chose to put the feud together around Summerslam I think that would've helped, but its also a question if Hade would've been ready or if he would've ended up like Jon Hendenrich. It is one of those perks of being a fans when you can ask what if and wonder how wrestling might have been different if something happened. Just to point out had this feud happened and went on to be Undertaker's mania match then its a question if Shawn Michaels and Undertaker would've done what they did considering 2009 was there first Mania classic.