Re: Queen cell failures?
There is a disease called black queen cell virus. Could be your cell finishers have a heavy infestation of it. Recently dead queen larvae affected with the disease can be largely white.
But the poor acceptance of your new cells could indicate any of the following. - not enough bees, bees not fed and conditioned well enough, wrong time of the season, not left queenless long enough prior to being given the cells.
And a common one, incorrectly set up cell finisher. IE, trying to finish cells between 2 honey frames, stuff like that.
There are other things can go wrong, but those are the most likely contenders.
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