Can you use a Lightning cable extension with an Apple iPhone dock? Can you use this:
https://www.amazon.com/Lightning-Extension-Cellularize-Extender-Available/dp/B073Z1G71S?th=1

with this?
https://www.apple.com/shop/product/ML8H2AM/A/iphone-lightning-dock-space-gray

The idea is that I'd be able to get a 3.5mm audio out for a headphone jack and be able to hold the phone in my hand. 

I listen to music, podcast, meditations, ASMR, etc., a lot and have high-quality (and expensive) wired headphones I want to use. I have tried multiple lightening-port charger + 3.5mm audio adapters, and all of them have failed. The Belkin one is the only one old on Apple.com and it too has horrible reviews, many people saying it fails after a few weeks (just like I've seen with other ones). Thanks.
YES, it works perfectly! Just be sure to use a good, quality lightening extension cable like one from Anker - or the Cellularize cable linked above on Amazon. Finally, a reliable 3.5mm audio + charging solution for my iPhone 7 (inside its Otterbox case)! :)