I forgot how many years we had been hatching so I had to go back and find my little blog I did on here when I joined https://www.backyardchickens.com/a/wabbit1964-harmony-hen-house.. So we got our first chickens in 2012 and started hatching in 2013. When they joke about chicken math and hatching...
Were these shipped eggs? Has it been a full 7 days? I would look very carefully there may be the beginnings of the veining there. Also you mentioned humidity what about temp? I know when my incubators run a few degrees low it makes my development behind schedule. Don't give up yet. I'd wait till...