I've corrected the second sentence in my previous reply.
If you received a distribution from the 401(k) in 2024 before directly rolling the remainder over to the IRA in 2024, you should also have received a code 7 2024 Form 1099-R from the 401(k) that will be included on lines 5a and 5b of Form 1040. That Form 1099-R would have the IRA/SEP/SIMPLE box unmarked. Perhaps you simply have not yet received that Form 1099-R from Vanguard. The code-G Form 1099-R reports only (or should report only) the amount directly rolled over to the traditional IRA and cannot include anything that was RMD.
