No, CyberDildonics is right - and asking the pertinent question. Strike doesn't denominate customer deposits in any kind of crypto. They're a traditional custodial wallet for fiat deposits, and a registered money services business. They appear to be using the lightning network to move money between Strike's own accounts.

They seem to use their own lightning nodes - that they don't allow third parties onto - to move money between their own accounts, rather than amending the centralized database of who owns how many dollars directly. However, it's all closed and internal, and I simply do not get why they would do this.