Aside from your correction which gives QGJ the edge the other two problems you have are that its not clear that tenacity down works as tenacity up. It seems to not reduce it for all toons to the minimum tenacity (15%?) but instead has a fixed percent reduction of N% which may or may not bring the Rancor down to the cap. I've experimented quite a bit with ES, TR, and QGJ with their respective potency (approx 50%/60%/100% for me) and still feel that there is a difference in resistance so they're not all having their effect apply at the same rate. It's just way too hard to quantify with limited runs and with T6 where the tenacity of the Rancor isn't high enough.
The other problem is that you are much, much more dependent on Tenacity down with TR. QGJ can work effectively with or without it while TR requires it to be consistently effective. While it is possible to lose TD as early as P2 with that squad if the Rancor likes Dengar for that particular night's Dinner. At that point you're effectively done with TR while with QGJ you can continue with just a reduction in efficiency.
My primary group is Teebo/EE/ES/QGJ/Fives. I have TR, Chewy, Phasma, and Dengar in a secondary group (assuming Teebo escapes) and find that they're plenty effective.
