I mean, it’s pretty straightforward. Go to reddit.com, click on your profile page, then on Comments. This will show you a list of your comments. If that list is empty, and it wasn’t prior to you deleting all your comments with an API tool like redact.dev, you can reasonably conclude that all your comments are gone. Yet it’s not the case.
I can show you a screenshot of the blank Comments page, but I’m not sure what it would add.