Is it an IRA account? What I’ve done with Ira withdrawals is enter a transfer to my taxable brokerage acct, and use splits on the table side to record the withholding. Not intuitive, but since IRAs are not taxable, I can understand why they are excluded from tax reports.
How are the tax withholdings shown in the Vanguard account? Please post a screenshot of one of the transactions, opened for edit,