If you've checked through everything and you're still not seeing the template, I suspect it could be some other problem with your settings/files rather than your overrides.

I re-read through your posts and noticed you've accidentally deleted and restored the "template_default" folder previously.

I'd suggest you install another zen cart store (e.g. shop) with a separate database (e.g. zencartshop) and then put your custom template there. If the new template shows up in your newly installed store, it means that your current store setup is somehow corrupted/mis-configured.

Try it and let us know how things go.