snowflake : copy into statement
the help notes:
VALIDATION_MODE does not support COPY statements that transform data during a load. If the parameter is specified, the COPY statement returns an error.
Which implies you are doing some form of JSON/Variant data processing in the COPY statements select. Which is valid without VALIDATION_MODE = 'RETURN_ERRORS'
So can you copy the data into a staging table, and do zero JSON process, to "just have raw data" which in a second command to merge/insert into a processed form?