Custom validation error for regex match

 I'm trying to apply custom validation to DOB. I have tested the regex match on regex101.com. It seems to work over there but fails to work in Qualtrics. Please help.
This is my Regex - [04]{2}\\-[2][0-9]\\-[0-9]{2}|[04]{2}\\-[3][0-1]\\-[0-9]{2}|[05]{2}\\-[1][0-9]\\-[0-9]{2}|[05]{2}\\-[2][0]\\-[0-9]{2}

I'm trying to check if user's zodiac sign is Taurus (April 20 – May 20)
For DOB I have used .QSF date picker file from Qualtrics community.