A traditional Russian headdress that inspired the shape and design of several actual Fabergé eggs.
It is highly probable that within the Russian fandom of this remake, "Kokoshka" was either: prison break kokoshka
Phrase analysis and likely meanings
If you are interested in the true story of how prison breaks work, or to find out if the series is still available to stream, please let me know and I can look that up for you. If you'd like, I can: A traditional Russian headdress that inspired the shape