Infertile call duck eggs, suggestions?

[CrittersNPets]

Ok, I have a 2 yr old and a 1 yr old gray call drake in a pen with a 1 yr east indie hen and 2 gray call hens about 2 yrs. They are in an above ground pen with a swim deep pool that is changed at least weekly, sooner if not raining. Last year the older trio did not have fertile eggs, this year I am the new owner and added the younger drake and our East Indie but none of the call or indie eggs have been fertile (leaving in incubator even past 10 days). I've incubated a few batches and the last batch the broodie Indie was on for over 2 weeks and all infertile. Both of the call hens have tried to go broodie but no eggs developed.
I tried a month of flock raiser, I've currently got them on laying pellets, I've at times added cat food or peas (but not reliably). My large breed Saxony (different pen) have had great fertility and I've hatched several of theirs just on laying pellets.
The older drake is a little grungy looking, not sure he bathes much. He and the 2 call duck hens are from a well known show breeder. They all seem content and get along. I don't have them in line of site so don't see them breeding (but don't see the big ducks doing it and they are fertile)
Any suggestions from more experienced duck breeders??

 

[country_girl011]

apparently if the pair never had fertile eggs theres an issue with the drake.
most likely hes infertile

 

[CrittersNPets]

apparently if the pair never had fertile eggs theres an issue with the drake.
most likely hes infertile

So, does that mean he isn't letting the younger drake mate? The younger drake is out of a different flock I hatched out last year. Will an older drake keep another drake from mating?

 

[country_girl011]

He could or he just doesnt get it.