I wouldnt be to quick to claim dronelaying workers.  Every time I found brood
above a queen excluder, it has meant that the queen somehow got into the
supers.

Possible reasons include:

1)  Bent wire in the queen excluder

2)  Impropery installed queen excluder (the queen goes around an edge inside
the hive).

3)  Queen is too small to be stopped by the queen excluder.

4)  Queen had laid eggs in the supers before the queen excluder was installed.

Incidentally, just let the drone brood hatch out.  If a nectar flow is on,
the cells will be refilled with honey as if nothing happened.

W. G. Miller
Gaithersburg, MD USA