Because that would be a financial windfall for Russia vis-a-vis international insurance and legal obligations to deliver gas to Europe.
The point of the attack was to hurt Russia financially.
Successful covert operations should not be made public.
The pipe line was repaired or not?
If repaired how many days to repair it?
Did Europeans freeze more due to less fuel available?
Russian Ruble has gone up, not down, since the pipeline attack.