I've kept an eye on mine since you've had this problem. Mine is good, but I've had the little clip that holds the sniffle hose on at the exhaust shield just aft of the sniffle valve fatigued and came off.
The pics in the manual show the hose having a bend in it, slightly; mine didn't have any curve to it. Not sure this matters, but the aft end of the sniffle hose is fixed to the fuse and the forward end moves relative the aft end. The clip at the exhaust shield likely didn't fatigue from the motion between it and the sniffle valve. But, it could have failed due to the same forces that cause your failure.
In my case I just removed the clamp at the exhaust pipe. The 90 at the sniffle valve will likely take the vibration better but perhaps will fatigue the sniffle more than the hose. Might be better to leave as is and re-clamp the aft end of the hose more forward, pushing a slight curve into the sniffle hose as it goes from exhaust to rear fastener. Would relieve push/pulls better than a straight shot?
For now I"m going to try it not clamped to the exhaust pipe. I suppose it could ride up and melt on the pipe?