The worst aspect of my experience was that by the time I knew for certain it was a scam (certain things he told me raised red flags, but didn't trigger a full refusal to continue), it had already costed me fifteen short of $300.
At that point and doing research following a bigger loss on top of that, I engaged in sunk cost action and simply told him "keep me updated on whether you can pull all that out to your Lightning wallet or not."
I was pissed; at both his falling for it, and myself being the biggest loser.