Hi Dominik,
Thank you for sharing the details privately. I was able to generate the Final URL Report for May 22nd, 2019. It looks like you're using different segment fields to pull the Cost metrics. The
segment fields are used to group the metrics. Including multiple segment fields will split the data returned into multiple rows. If you use
incompatible segments (ClickType) this might not return values. I made a few changes to the report query to segment based on AdNetwork Type or Device and I was able to pull the Cost metrics.
Hope this addresses your concern. Let me know if you have any questions.