I dont know if this is the right place so let you know this, but here I try.
On your " Zwift Academy Known Issues" page it says to contact you if you havent been credited for workout 4 i Zwift Academy because you have a workaround.
I have only got a 25% completion rate after doing 4 of 12 workouts. Did W1 29/10 then 2 and 4 on the same day 01/11 and W3 today 02/11. I dont know if its workout 4 whos the bad guy in this, but now you know. It allso says I have done W5 on the 01/11 with 11 of 21 stars but I havent done it yet.
If the workaround is patience I will be cool as ice 
Thanks for the good work you all do at Zwift.