"They Conflict with each other,"

What does that mean? They are each separate and stand alone. A W2 and a 1099-B are separate reporting forms.

The W2 has the taxable value at issue/vesting, so that is Basis.

The 1099-B is because someone sold some of this. That happens, for instance, to cover the withholding taxes due on the vesting. The employer might have a provision to do this inhouse, or they outsource that to a broker. Or, the owner sells later. Either way, it's the same as any sale.

You don't enter the same one twice. Enter the W2. Then enter the Sale, no differently than if any other stock other than the employer's stock, was the sale. Yes, you have to provide this person's basis from their vesting value and date(s) if it isn't provided.

And yes, you keep starting new topics, but it's the same community you already asked. It helps to keep it to one place, so everyone can see what is already being discussed and provided.