The group behind this hack, called “Gonjeshke Darande", threatened to release Nobitex's full source code after they hacked and stole > $80m from the exchange. So apparently it seems like they have actually done that and made good on their earlier threat, as they have published the exchange's full source code, creating further risks for users of the exchange who still have funds in there.
https://cointelegraph.com/news/nobitex-hackers-reveal-source-code-after-100m-hackWhat about those wallets that are very open source, what I think is that it can be easy for people to clone the website which is the risk about it that I see, bit I do not know what they mean as the internal files, I think only the code was shared but no internal files shared? I think they want people to panic and withdrawal their money on the exchange is what they are doing.