Hi Efthimis,
Thanks for reaching out. With regards to your concern about to retrieve the campaign's information from gclid, You can use Click performance report with gclid field and you can get the campaign id from the click performance report but in this case it wont return the proper campaign id cause its an app campaign. Currently UAC information and anything related to them, can only be retrieved via the reports listed in this guide.
Let me know if you have any questions.
Thanks,
Nirmita Patel Google Ads Team