I doubt you can. If the data collection is illegal under the GDPR (or it’s incarnation under danish law), then it won’t help if you don’t use it in a public fac

I doubt you can. If the data collection is illegal under the GDPR (or it’s incarnation under danish law), then it won’t help if you don’t use it in a public facing context. The GDPR doesn’t make any difference between subjects that are employed by the entity collecting the data and others.