Consent for processing children's data in the EU

Please give an overview of the topic you wish to discuss, and your particular situation.:

We are a Market Research firm based in ***. We conduct market research surveys on Gen Z and Millenials (13-39) and just moving to international data collection. We use panel providers so do not have our own panel of participants. I'm trying to write our first Privacy Notice and am struggling with stating rights for revoking parental consent to processing of children's data. While we collect sensitive information like (gender, age, ethnicity, etc) we do not collect email address, names, addresses which would be personally identifiable. Howevever, to ensure data integrity we do collect IP Address automatically in our surveys along with other geolocation data. This is only used to ensure survey participants are truly from where they say they are from and that they are not repeat participants for that particular survey. After the survey is complete and we have reviewed for accuracy we remove that information from the data rendering the other data anonymous. If we tell them they can withdraw consent even within that 14 day period though the likelihood of use locating the exact record for that respondent is very slim. Is it ok to state that? For example: "If the legal basis for processing is parental consent you have the right to withdraw your consent for processing. Due to the limited information we collect, however, location of the data may not be possible. However, we will make every effort to do so. If you wish to withdraw consent to the processing of your child’s data please email ***."
Any help greatly appreciated.