To be honest, I've never heard of Cashaa crypto exchange. Why would a person use a barely known exchange when there are multiple reputable ones out there? If an exchange is popular, there is a higher chance it will have a way better level of security. Plus, if it's reputable, there's a good chance the losses will be compensated to users (which is what happened with Binance a year or two ago). And what sort of exchange stores money on Blockchain rather than in a cold wallet?
My number one source of learning about obscure exchanges is when they rape their customers. It's a dependable stream of information.
I'd never heard of them before either.
From the looks of their site -
https://cashaa.com/business-account -
https://cashaa.com/personal-account - they are primarily about providing conventional banking with crypto integrated as a sideline. Many people, especially businesses, are desperate for banking so will go with anyone who offers it and makes crypto friendly noises.
The exchange is from some Indians and the alleged hack is also from India. It could be an insider job. I don't mean that the exchange itself is involved but maybe someone that is working with or had worked in the past with the exchange that had some inside knowledge as how and where the funds are kept. Indian police have an experience of investigating hacks in the past, I hope they get to the hacker this time too.