"So it looks like the 1099-B was reporting the correct cost basis after all. It's curious that TurboTax didn't bring in this number for some reason when I imported the 1099-B."
That would depend entirely on how the broker set up the import file; it's not necessarily a mirror image of the paper copy. If the basis really is in Box 1e of the paper 1099-B you might look closely at the 1099-B to see if that basis is really being reported to the IRS, or simply to "you." I would guess the latter since the imported version had $0 in that box, which is all that the broker is required to report.
"FYI...I found that the closing price on the vesting date was significantly different from the FMV used to calculate the cost basis and compensation."
Not sure what "significant" means in terms of dollars here. If the stock happens to vest on a day when the stock price fluctuated wildly the closing price certainly could be quite a bit different than the "fair market value" used by the employer. I would expect that number to be somewhere in that day's High-Low range, however.
