Zatko's claims will undoubtedly help Musk's case. He has argued that "Twitter executives don't have the resources to fully understand the true number of bots on the platform", and his claims over security vulnerability may provide Musk with another argument that Twitter has misrepresented itself by violating its 2011 agreement with the DOJ and FTC.
This will do nothing to hep Musk's case. Downturns that have followed these revelations are an overreaction - even if Zatko demonstrates that spam accounts made up 6% or 9%, rather than 5% of overall accounts, it would not prove Musk was sufficiently misled to enable him to back out of the purchase.
The timing of this can't help but raise questions. This seems like a classic example of an opportunistic former employee. Zatko was fired from Twitter earlier this year due to poor performance and leadership, so it makes sense that he'd try and tear down the company that released him from his once-prestigious position.
There's a 35% chance that personal ID authentication will be obligatory for new Twitter accounts on July 1, 2023, according to the Metaculus prediction community.