The public USCIS E-Verify pages provide a report of employers using E-Verify. However, this report only shows that the employer is enrolled in E-Verify. It does not confirm that the employer actually uses E-Verify. There is also no way for a third-party such as a state to confirm the employer's E-Verify Company ID.
It would be most helpful to include the employer's Company ID as well as the number of cases processed in the current calendar year (or government fiscal year). States that require employers to use E-Verify have no way to confirm the information an employer provides to the state regarding the use of E-Verify.