This is what my contact actually asked me to ask you when I relayed the message, for you to show the proof in form of your bank statement from the date of the said withdrawal to today. Do you mind to send it to me, if you trust me? I will assure you that I will not use that for malicious intent, I'll just relay it to my contact.

Otherwise, you can also send to BC.Game Support [who, by the way, is here giving response as per your request], if you're concerned about privacy and sharing it with third party [me]. I believe they'll forward that info to my contact, and will make sure they do that by telling my contact that the staff who handle the BC.Game Account has that info sitting in their inbox.