Those are model numbers, not firmware versions. He lifted that from this Krebs artical (https://krebsonsecurity.com/2018/05/fbi-kindly-reboot-your-r...) which is also wrong.
All Mikrotik products running less than version 6.38.5 are vulnerable: https://forum.mikrotik.com/viewtopic.php?t=134776
It makes me wonder what else is wrong....