I have no idea, but that doesn't stop a person from making a judgment call.
If the roller weighs 920 pounds, it will weigh more than that to pull it- there will be ground resistance, especially if the ground is soft. I don't think zero turn mowers are really designed to pull- they are designed to mow. I would imagine that the hitch on the back is for a sweeper or spreader, not something super heavy. If the mower were mine, I'd ere on the side of caution and not try it.