I am also a Dual Spork totem Templar and I have no problem soloing Cruel difficulty. What kind of support gems you use? Do you have summon skeletons + Summon Zombies + Summon spectres ?
I link Summon zombies, summon spectres, summon skeletons with minion life support gem.
I link fork + spark + spell totem+Faster Projectiles
I also support my minions with Discipline and curse mobs with Conductivity.
Basically I just cast 2 totems and stand there waiting for my army to kill everything.