When you want to display a record, you can aggregate the data historically and allow people to see changes and attribute them to users and time but you can always see what was originally added.
However that's kinda risky for HR because anything committed to that DB will be there... forever!
The forever problem can be, ironically, resolved with crypto. If you encrypt each employer record with an employee key then, if the employee data needs to be deleted you just delete the key and the data is gone.
One problem with sharing data between multiple parties is that you need somewhere central to store it, somewhere that's ultimately trusted. If you decide to trust one party, they could still make mistakes, have downtime, stop supporting the project that requires the shared data, or go rogue.
I'm perhaps too ignorant of blockchain, but could it help with this scenario? Does it give a better promise of availability and more trust in its consistency and integrity?
edit: I'm thinking here of a blockchain whose only users are this group of companies, not a public system. I don't know if a blockchain becomes useless when it is only used by a small group.
in a distributed, trustless fashion
If it's not distributed or trustless, you can do the same without the blockchain.
Git is why people like blockchains so much - the value is clear, since it's what we interact with all day.
A blockchain takes that trust assumption and spreads it out amongst the social consensus of the chain, so re-witing of history could only occur if there is a consensus to do so.
Send me a hash as new data is added to your DB and I cut you a cert... the next cert includes hash of the last cert plus the new hash you just gave me...