I take it they suggested using nitromors to separate the polymer & microban from the cement? It is also something that you need to do with ultracolor plus to separate the polymers. Otherwise any acid cleaners fail to work effectively.
Nitromors turns opaque when in contact with water, if what you have left is not opaque, smeary phlegm looking stuff then I'd doubt it was remaining nitromors, more loosened grout polymers or slurry residue from the factory wax used on porcelain that have been partially disolved by the nitromors.
Pretty much any alkaline cleaner should tackle the wax, you could try calling someone like LTP who might be able to point you in the right direction.