@Tj2008 , if I understand your situation correctly:
(a) you were allotted some shares by your employer at an FMV of US$100
(b) Employer reported this award of US$100 on your W-2; Employer withheld taxes of US$ 30 towards taxes ( Federal. State, FICA ) all shown on your W-2
(c) You wrote a check to the employer covering the taxes withheld.
This would mean that the employer took your check to defray the taxes ( Federal + State + 1/2 FICA). So all you have to do is o confirm with the employer that indeed you paid for the taxes and not directly withheld from your pay. If that is correct then there is no issue -- your W-2 is correct. If on the other hand the employer withheld from the award ( how, -- your net pay would have been reduced to pay for this) then you need a corrected W-2 to show this extra withholding.
Does this make sense ?
