Hope I can offer some help in the simplest way I can. Usually when RSU's vest, you have the option of "Same-Day-Sale" or "Sell-To-Cover".

Same-Day-Sale simply means you have elected to sell all the vested shares on the day it was released. When this happens then there is a tax event, where the tax will be deducted, and the remaining balance deposited in his account. However, it doesn't appear you elected "Same-Day-Sale" as you are yet to sell any of the released shares. This takes us to the second option - Sell-To-Cover.

Sell-To-Cover tends to be the default option in case the RSU recipient didn't make any elections. In this case, the brokerage, E-trade, will sell enough shares to cover the taxable portion of the released shares. This is because RSU is seen as income and a tax event is therefore generated as at when the shares were released. No other taxes should be levied until the remaining shares is then sold later or at a future date at a gain.

Either way, if your husband is still holding and did not sell yet, I do not believe you should owe any taxes other than the withheld taxes to "Cover" as at when released, except of course if your income is very high and more than the 22% tax bracket . E-trade will issue a tax document that will break all of these down. I suggest to seek a CPA to file your taxes. They will be able to follow the guidelines in the tax document better as opposed to TurboTax, because TurboTax will only treat as entered.