Hi Petros,
To help me understand your concern and for further investigation, could you provide the complete SOAP request and response logs that were generated when you ran the bid landscapes? You may provide them using the Reply privately to author option.
You may take note that with bid landscapes you can examine performance statistics for the past week at the current level of bidding, alongside simulated performance over the same time period using different bid amounts.
If you would need further confirmation on how estimates are being done, you may also check with the
Google Ads Community Forum as they may provide further insights on this on the product level perspective.