HELP! Non recognition aggression, nothing helping!

I have four neutered cats, 2 boys, 2 girls. Fve days ago, one of my boys, the Alpha, Ziggy starting being very aggressive with the other boy, Sammy. Turns out that Sammy has a urine infection, meaning he smells odd to Ziggy, thus triggering non recognition aggression. We're now on day 5 since it started, and Ziggy is still being really aggressive with Sam. I've tried separating them, rubbing each others scenet on them, vanilla essence on them both, giving treats for eating close together. Nothing is working, and we're all stress half to rather. Ziggy has already turned one of my girls into a scared cat with aggressive behaviour, and nothing has solved that problem either. We've tried drowsy plugs and collars, homeopathic remedies, Spirit essences, even Clinical, but all to no avail. My girl more or less lives in one room as she's now petrified of Ziggy. I can't bear the idea of the same thing happening with Sammy, as he and Ziggy have been friends until now. ANY ideas as to what on earth I can try next to restore calm would be greatly appreciated.

Is Sammy still on meds for his infection? Perhaps the smell of the "vet" upsets Ziggy. Once Sammy is well, you may have to reintroduce the boys. 

Yes, Sammy's on Antibios for another week.Though this has not been an issue with Ziggy before. I'm trying to supervise access between them so Ziggy doesn't completely forget who Sam is, but the situation is very tense.Ziggy is very wary around Sam and follows him all over, sitting watching him intent. POOR Sam is nervy around him, understandably so after having being attacked by a screaming Ziggy several times. I'm so hoping that once He's off the meds things may improve, but right now it doesn't look very hopeful.