you must use different versions on the two platforms. There was a change some years ago regarding default glare source detection mode from 5-times average luminance to a fixed threshold of 2000, based on the findings from Clotilde Pierson. Things like this (default values) are always documented with the manpage shipping with the version.
So please check the versions that you are using by evalglare -v and post the versions you are using on both platforms.
The above mentioned change was to version 2.05 in August 2018. If you use an older version on any platform, then you should update.
In case you have exactly the same version for both platforms but different results, then please share that image to me so that I can investigate this further. But I never experienced different results - at least not for the versions that I compile myself for windows (which is a different process).