Help sexing Mandarin ducklings

[ValleysPoultryWaterfowl]

I hope I'm not seeing all drakes? There's 1 that may be a hen. They are roughly 1 month old, maybe a few days past. Hopefully I'm wrong lol. Tried to get different exposures as bills look different color, depending. Any thoughts? Thank you!

 

[MGG]

I'm only seeing one possible hen but that's just because I can't see the bill well enough.

Four front ones are all drakes for sure.

The hens do get a bit of rosy color when they mature sometimes at the corners of their bills but that usually doesn't show up until later.