What 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, 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.
After provoking damages as big as close to 100 million dollars, the next move being leaking the source code so everybody panics and withdraws their Bitcoin sounds like a pebble in the ocean.
They likely released the source code as an incentive for other hackers to join in and find vulnerabilities, ultimately provoking even more damage to the customers or to the exchange itself.