How to prove the funds are from trading, of course this is hard to prove, though to prove that the funds are there and that we are not running under a Ponzi structure, that is the purpose of our transparency.
But it doesn't prove anything. You can just as easily accept deposits into one address while making fractional payments of 'profit' out through the other balance in order to operate the ponzi structure.
Ponzi incoming deposits are lump sums coming into one address.
Ponzi 'profit' payments are fractions of those lump sums being sent out.
Whether it is happening on one address or two the only practical difference is that you already set up a credit balance with 'your own' funds before you launched. Exactly the same scam is taking place in both scenarios.
You'll send a few fractional payments out from that address , sure, but you'll end up stealing the majority of any deposits you might get into the other address.