Thank you for the request. Yes, the cache logic in the GroupDocs.Comparison is same as for the GroupDocs.Annotation but with one difference The folder name for the current comparing cache files is taken from the “.ResultFileName()” property, it’s mean for example you compare two docx files and result file name is “Redline.docx”, the cache files will be stored under <root_storage>\temp\Cache\Redline.docx\ and <root_storage>\temp\Processing\Redline.docx\ .
Since that in case that you will use same result file name for all comparisons you not need to clean the cache folder from old files - they will be rewritten.
From other side you can use approach from earlier thread (link that you shared with us). The logic and code is same you only need to keep in mind that the result file name will be taken for the path combining.