We don’t give very much value to the shadowgrasp totem’s healing effect for tanks. So when you are using a “mostly TUF” gearing strategy, that is effectively a DPS trinket effect that has almost no value defensively.
Stamina is a good defensive stat, so I’m not surprised that some stamina trinkets show up in a mostly toughness set of gear. The effect on that trinket from tazavesh has an absorption effect on it too - and absorbs are generally some of the best effects for tankiness.
Blizzard does not design very balanced tanking trinkets/effects, so it’s not too surprising to see the recommendations all over the place with respect to item level.