I believe Bradford council own the stadium and lease it to the stocks people who then sub lease it to the rugby. If the council/rugby club don't get this ambitious project off the ground, the rugby club may look at more modest alternatives elsewhere.
The track is too narrow to meet FIM standards. The only way they could widen the track is if the rugby club left, which is not out the question because I don't think they are happy with how narrow the rugby pitch is.