JYNNEOS should not leave a scar behind.
It is possible some jurisdiction is administering the ACAM 2000 vaccine, which, as you noted, do leave a scar behind.
"Jurisdictions may also request shipments of ACAM2000 vaccine, which is in much greater supply, but due to significant side effects is not recommended for everyone."
https://aspr.hhs.gov/SNS/Pages/JYNNEOS-Distribution.aspx