The hit row gives the toy secret exponent.
The table gives the exponent
Once the target row is found, the attacker has x=6.
That exponent was the secret
The public value y hides x only when the group is too large to search. Here the table already found it.
gxmodp=y
The target check still holds
The recovered exponent maps base 5 to public value 8.
56mod23=8
Summary
Recovering x turns the public DH value back into the toy private exponent.
private exponent=6