Have you checked FortuneJack?
I heard before that they also accept Lightning Network in transactions made.
On their website, there is no options deposit or withdrawal using LN even on the new beta website.
I like LN transaction but I heard many people complaining of it. But for me, it is quite good if we can reduce transactions at a low cost without worrying about the transaction speed and also without making any contact with the main Bitcoin blockchain but the only transaction can be a trace on blockchain.
Anyway, I bookmarked this for future reference.
Because not everyone really aware with LN, most of the user only a user with basic information about cryptocurrency like trading, creating a wallet, sending and receiving. They don't really know about how to set up a node for LN, etc. The maximum transaction LN can handle around 0.16 BTC according to some thread Reddit, so could be a problem for someone who wants to withdrawal with a high amount.
But the main problem still on the knowledge of the user, since not everyone is really a bitcoin geek.