What happens if the scorekeepers run out of numbers?
Central banks are the originators of money, itself a socially and legally recognised measure and transactor of debts. There is no resource constraint on supply.
Trust may fall, inflation may occur, there may be too much money chasing too few goods and services. But it's largely axiomatic that a central bank cannot run out of money.
Regionally, some preferred currency may emerge, but given that a pandemic is literally everywhere, there are no regional banks which are entirely unaffected by the situation. (Some may be to a greater or lesser extent, and regional trust shifts might occur.)
But addressing your hypothetical; that's definitionally impossible:
A central bank, reserve bank, or monetary authority is an institution that manages the currency and monetary policy of a state or formal monetary union,[1] and oversees their commercial banking system. In contrast to a commercial bank, a central bank possesses a monopoly on increasing the monetary base in a financial crisis.
https://en.wikipedia.org/wiki/Central_bank