Filename Matching - Custom Date not Matching

I have an issue that I cannot find an answer with Professor Google or by searching this forum. I am trying to rename files that have the YYYYMMDD format to the YYYY-MM-DD format. When I setup the conditions for the rule (Filename: 20200406 Some Specific Name.txt), I use the Name Matches condition with the Custom Date Token. If I keep the "Automatically detect date format" checkbox, checked it matches, however, if I deselect it and use the (1999)(12)(31) pattern, it does not detect it. Further, if I use the Custom Text Token and use any of the single character patterns, it also does not match. I have also downloaded other people's hazel rules which report to solve the same issue, but they do not match either. I do not want to use the Auto Detect feature, as it would also find correctly named files (YYYY-MM-DD).
This is baffling me as it seems that it should be way easier than all the other rules I have defined in Hazel. Any assistance in how to troubleshoot the rule condition (I am using the Preview option now) would be greatly appreciated. I have years and years of files and as many file types with various naming conventions used by various members of my team. Thanks.
This is baffling me as it seems that it should be way easier than all the other rules I have defined in Hazel. Any assistance in how to troubleshoot the rule condition (I am using the Preview option now) would be greatly appreciated. I have years and years of files and as many file types with various naming conventions used by various members of my team. Thanks.