if bitbills.com is shut down, then bitbills are worthless.
That statement alone tells me you know nothing about bitbills.
The Private wallet keys are embedded in the bitbill. Even if they got shut down you could still redeem it.
That wasn't a categorical statement, it was contingent on the premise that bitbills are only redeemable by software only provided by bitbills to convert from the card back to electronic. I want to know how the Private wallet keys are embedded in the bitbill. If I buy a bitbill, how do I scan and convert the bitbill to bitcoin if bitbill.com is no longer available?