Seems like in recent years the channel where those "rollers" are has narrowed. Either that, or the rocks on river right have moved around a bit.

At the angle you have take with a 17ft db to avoid the rock (or the big hole, depending on cfs) there just isn't much room to screw up. Doubt it would be much different backing it down...

It'd be worth every penny of $500 to watch someone "try", imho...