Wado,
Never dilute fungicide, as you could be inadvertantly creating a more resillient strain of fungus... that would be bad.
The fungicide I personally use, is the Clearys3336 offered here on the site... (under accessories) but I have not had cause to use it on anything but plants I was putting into dormancy. It is very strong, industrial grade, and will kill any fungus you might be having a problem with. (And it stinks to high heaven... but all fungicides do)
ANy how, how isw your plant still looking sick? It is quite possible that it is still adjusting to it's new home... give it time... The old tissue on it may not be hardened to the new environment, or it could be fine, but the damage already done, it could be shock, it could be that today is an odd numbered day of the year... as long as new tissue is growing, then your doing good...
Question though... is the new tissue equal or close to the size of the old stuff? meaning, it's not producing radically different sized traps right?
If your plant has long leaves with large traps, and is not producing a tiny rosette of leaves with very tiny traps, then suprise, your actually dealing with a new plant!
In which case, I personally would just leave it until it is old enough to carefully remove the husk of the parent.
Your growing on a window sill now right? if so.. I doubt your humidity is high enough, and the air stagnant enough for fungus to set in... but if you kept your water to high in the tray, you could have rotten roots in the one... just a thought... don't mean to alarm you!