@joesegal,
LifterLMS doesn’t actually output this information. Most themes treat custom post types like regular blog posts (lessons, certs are both custom post types).
So more than likely your theme is simply treating this custom content like a blog post.
Some themes let you customize this but that means that if you do that, you’ll need to hide the author output from your blog too (that may not matter to you, in which case that’s your solution, find your theme blog post settings and turn off author information).
If that can’t work you can visually hide the output with CSS. You can reach out to the theme developers for help with that and if you have access to LifterLMS email support you can submit an email support ticket and we can take a look at this for you and provide you with a small bit of CSS to help out.
Hope that helps,