You will not hold your own defense. I repeat, zQGJ is terrible on defense.
That being said, you should do as you please. Just know, QGJ's zeta will not provide any benefit on defense at all.
There is a player on my shard who runs QGJ, Yoda, Ani, Palp, and Shore. That would be a team to work towards. Honestly, all of your choices aren't that great. An auto tank would be best. B2 or Palp would be okay. I tried Ashoka with GK lead but that didn't work out too well. QGJ lead might be better for all I know. If you choose Rex I'd lose Yoda.
I'm just not seeing any viable options at this point. I'd save the zeta.