I recommend to encrypt your games when uploading to Google Drive. Google is
known to hash-scan uploaded files looking for pirated content, which applies to GOG game installers since they are widely distributed in piracy circles, i.e., if the oficial Witcher 3 installers from GOG are flagged for some user sharing the installers, then Google flags all copies of that content everywhere. This might become a problem for you in the future, with the risk of account cancelation due to violating Google's terms of service.
I recommend
https://rclone.org/ since it interfaces with a lot of cloud services (including Google), and you can setup the encrypted storage of your files transparently. What this means is that files in your computer/storage remain unencrypted, but rclone encrypts your stuff when you upload, so that it rests at the remote storage in an encrypted form.
This is what my GOG installers look like in Google Drive (a garbled mess):
And this is what rclone shows when I access Google Drive:
If you want to go full autistic, though, check my post earlier in this thread:
https://rpgcodex.net/forums/threads/gog-com.69065/page-462#post-7052838