mutiple date formats in snowflake during copy

COPY INTO MY_TABLE (NAME, DOB, DOD, HAIR_COLOUR) 
FROM (
   SELECT $1, TO_DATE($2,'YYYYMMDD'), TO_DATE($3,'MM-DD-YYYY'), $4 
   FROM @MY_STAGE/mypeeps (file_format => 'MY_CSV_FORMAT') 
)
ON_ERROR = CONTINUE;