Holikme 30 Feet Dryer Vent Cleaner Kit, Flexible Lint Brush with Drill Attachment, Fireplace Chimney Brushes Extends Up to 30 Feet for Easy Cleaning, Use with or Without a Power Drill

You've done a lot. You can pull the hose off and make sure it is clear. You can get a device like this and clean out the entire pipe. https://a.co/d/00yGjB0W

I got one of these https://www.amazon.com/dp/B0C4V5LWWL and then something like this https://www.amazon.com/Holikme-Cleaning-Remover-Fireplace-Synthetic/dp/B07SQYX2FH/ and blue taped the camera to the rod, without the brush and fed it through to get a look. There's an app on the cellphone (I'm on Android) that you can record the video. You might tape the nylon rods together because if you turn them the wrong way they can unscrew inside the vent, which would be very bad.

Get one of these or something similar and attach it to your drill you'll definitely clear it out https://a.co/d/0eFByEga