Different states have several types of Deeds available.
In Michigan we use Warranty Deeds by default. Not sure how that works with P.E. but it's more protection.
https://openescrownow.com/know-types-of-deeds-and-taking-title-in-california/
I sounds like 'Owner A' has been legally bullied enough by 'Owner C' that they are moving instead of fighting.
Owner C is rich and stupid enough to waste gobs in legal fees instead of fixing his/her own problem.