Are the tokens a senior claim on any of their assets, though?

No. The CEL tokens are not securities, and do not represent any debt or equity. CEL holders are not entitled to any claim on Celsius' assets.

The CEL token's sole purpose was as a tool to offer users promotional rates (and maybe for a bit of insider pump-and-dumping).

that's not true. They claim the CEL Token as an asset. It should be a 5.3B hole.

I don't understand how that contradicts what I said. CEL token holders are not entitled to any of Celsius' assets, like shareholders or bondholders would be.

That's a separate issue from Celsius owing their depositors CEL as a debt. Those CEL creditors are entitled to Celsius' assets through the bankruptcy process, if Celsius cannot otherwise make good on that CEL-denominated debt.