So sorry to hear of the loss of your wife.
To solve your problem, you need to file form 5405. Check box h in Part I indicating that the homeowner has died. When one of the owners passes away, their portion of the first-time homebuyer credit repayment is forgiven.
To add Form 5405 in TurboTax, follow these steps:
1. Sign into your account and select your current return
2. Select My Account and the select Tools
3. Select Topic Search top left
4. Search for 5405 and select go
This will take you directly to the interview for this form.