> Can we not deal with those issues ourselves

No, an individual labor seller would never be able to gather the information necessary since they experience so few transactions.

How can one expect markets to work without price transparency? Labor buyers have access to far more price data than labor sellers, which tells them which way supply and demand is moving, giving labor buyers an upper hand.

If you want labor to be allocated most efficiently, then labor sellers also have to have access to labor price data.