TL;DR: even if your delete script confirms a full wipe and your Reddit profile page shows zero comment, there may still be comments left over (that you can find through a search engine and delete manually on Reddit)....
I deleted my comments last week but its like you say, they still show up in the threads on reddit.
How do i make sure these comments are properly deleted? Weird thing is the comments showing make it look like i deleted my account, and not the comments, which is not the case. I still have my account, i only deleted my comments and posts.
I just found out that not all of my Reddit comments had been deleted despite my profile page showing otherwise. ( kbin.social )
TL;DR: even if your delete script confirms a full wipe and your Reddit profile page shows zero comment, there may still be comments left over (that you can find through a search engine and delete manually on Reddit)....