Unexpected File Format .skp and .skb file

Hi! In my architectural firm we work with SketchUp and Lumion, one of our files shows Unexpected File Format for both .skp and .skb. I would appreciate your help to retrieve the model of the scene, that was few hours from being finished. I tried multiple times without success.

The files are here
https://drive.google.com/drive/folders/1bTyMhZYSL8aQS4RtQHtMl7Jfr9Kg2eA1?usp=sharing

Thanks in advance

I have the components in the file recovered, but the file is a lot smaller. I have asked a developer to try to recover more from the file.

Thank you so much Colin!