1) Romania adopted the Gregorian calendar in 1919. There are 12-13 days difference from the Julian used.
2) The date in the birth ledger is the date when the entry was made by the Civil Office clerk. Usually that is 1-2 days from the DOB but that day is always mentioned. Unless you have a picture of the actual record, it is unclear what the Archive transcript has provided.
3) A discrepancy of the size mentioned is very small. In most cases (thousands) I have seen, the date, and even the year in the US records does not match the actual DOB.
Great Neck, NY