Seriously? A Casino requires a requirement like this? Because it is very private, mate. And what does it have to do with having to provide an income statement from your electrum wallet to fulfill KYC in a casino? I'm curious, what casino is that?
Have you just won so much that they require a requirement like this? If not, then I'd rather forget about it and move on to another casino that doesn't require as much data to fulfill KYC.
However, if they do require the history, then use the history tab or a website to search for transaction history such as blockchain or blockchain explorer from your wallet.
Maybe you are not really a gambler because you are not aware of this things yet but I think this also exist on almost any services that requires a KYC (preferably the ones that are in higher level already). If you think this was very private, then what about when you submit your ID, phone number, email, selfie, etc...? Aren't you surprised with them? In fact, I think they are more private than this one. We should not worry.
As long as the casino is known to be legit, I'm sure that they will keep our details securely and privately. Like its name says (income statement), I think they want to make sure that the source of our funds are from legit sources only. They are also being careful and they are afraid that they might get in trouble because they allow criminals to play on them. This doesn't has to do with winning a huge amount of money but winning a huge amount of money triggers a KYC.
If so, simply providing your public address would be enough, since all incoming and outgoing transactions are recorded on the blockchain and available for anyone to see.
Good luck, and if you can provide us with more details than what was requested, it might be easier for us to help you.
Yes that was it. I already came across a requirement like that on some casinos that I've tried. Casinos are too sensitive on this, so what you are suggesting there is not going to work. Also, there are cryptos that are more private than the other.
However, what I believe they want you to prove is how you acquired all those bitcoins, whether you have a job, whether you earned them in an old ICO trade or bet, etc. But if your source of income is an old bitcoin HODL, then the blockchain records will indeed be your greatest ally as proof.
If let say this was acceptable and if it was a Bitcoin HODL (whether old or new), I think the ones we will show is the transactions from the exchange, wallet, etc...