Do you mean that it smells like mold or that it smells like plastic?
You don't have to use an Apple cable since they've gone with an industry standard. I rarely use any Apple OEM cables on any of my devices now. I'll use cheap USB-C cables from dollar stores or sometimes cables I bought from Amazon . If it doesn't work I'm not out a whole lot of money. Any iPad model that uses USB-C doesn't need more than a standard 3A rated cable for charging. But then it gets complicated because of transfer speeds (I believe even Apple's 2 m charge cable is only at USB 2 speeds. You would need a Thunderbolt 3 cable (also doesn't need to be Apple) for faster speeds. Apple's is fairly short and costs twice as much.
About the Apple Thunderbolt 3 (USB-C) Cable - Apple Support
As long as you didn't noticeably damage it, Best Buy has a pretty generous return policy. Looked it up and it's 15 days.
I've got a variety of cables I use with my mini 6, but I've been impressed with the ones from Monoprice. For your applications I'd recommend the Stealth series, although I've had good results with their Essentials series too.
I've bought this specific one because it was 10 ft at a good price. It will probably be used with a computer.
https://www.amazon.com/Monoprice-Stealth-Charge-Type-C-Cable/dp/B088HZY5CM/
For this you can play around with color, length, power, multipack, etc. and find different prices. The prices don't necessarily correlate all that well. Sometimes a longer cables in a different color is cheaper. There are a lot of weird options including some pages that have a single type and others where you can select different lengths/power/color.
https://www.amazon.com/Monoprice-Stealth-Charge-Type-C-Cable/dp/B088J32PB6/
https://www.amazon.com/Monoprice-Stealth-Charge-Type-C-Cable/dp/B084HP4WCV/
