We, as a community, can't interact with this topic more than consider it a claim because wrote it and deseappear without providing a single proof or follow the report format. Op, aren't you interested in your topic about half a million dollars? Or the case has already been resolved right after posting this thread? Strange behavior.
By supposing the story is true, I see that withdrawing this big amount might exceed the withdrawal limits. I am not a Whale.io user so I can't tell exactly about their withdrawal limits. By searching the web, from a rating website, it is mentioned that withdrawal limits are 50,000$ but without to mention if it is daily or monthly:
Maximum withdrawal is $50,000, although not specified whether weekly or monthly. Most payouts clear after one internal review, then move on the chain. For small and medium amounts, this can take a few minutes. There are no withdrawal fees from Whale.io, but you do pay network gas on each transaction.