I just saw this post but Nikitski Ranni is the same as Crimson Sky.
I am in Fairfax County (7a) and have both Salavatski and Nikitski Ranni in the ground and they have generally grown happily for me but I don’t have fruit this year.
I previously had a Nikitski Ranni at a different house and it fruited for me there and was tasty but the seeds are more noticeably crunchy than the popular commercial varieties.
Here is a post I made showing one of its fruit back in 2018: