No problem, sure hope the info helps, and also hope that you kick it. I'm undoing my own main tank infestation issue currently so I'm with ya! (Hyposalinity for Ich).
By the time external symptoms show with most pathogens, it often is too late and you can be 100% confident that all of your fish have some level of disease. Especially if fish died in the tank already - when this occurs, there are less hosts for an equal number of pathogens in the tank (which means the living hosts will have an increased attack from pathogens that leave the dead tissue in search living).
I've never used Kordon. If it were me and I was confident this is Amyloodinium (which kills everything, quickly), I would do as Steven Pro suggested and jump straight to QT copper ASAP on all fish. And run fallow (inverts included) for 8 weeks at elevated temperature (see wetwebmedia page on this condition). I've been through enough disease and medication runs that I wouldn't want to prolong expense/misery of main tank infestation.
If your other fish shake off spots and come through, your probably aren't dealing with Amyloodinium. More likely it is Ich, and personally I would do hyposalinity. This is why diagnosis is crucial. If you had known deaths from Ich before, you may be dealing with it again. The Ich population could be running its lifecycle, which has flare-ups and quieter periods.