Sorry I got thrown by "longer". Ok so you need something that can reduce the length even more than the ride2 offers.
Googling the ride2 indicates it can reduce up to 76mm correct? How much shorter do you think you need?
Here's one that reduces up to 85mm:
https://t-cycle.com/products/easy-knees-crank-shortener
Here's another that reduces up to 88mm:
https://highpath.co.uk/cycle-crank-shorteners/
The same company offers to shorten existing cranks down to whatever length you want:
https://highpath.co.uk/crank-shortening/
Here is somebody stateside who will do the same and more:
BikeSmith Design and Fabrication
If you are feeling DIY you can tap a second hole farther up the crank. And then mount your existing shorteners from that point?
When the kids get bigger you can remove the shortener and mount their pedals in the second hole. Larger stokers can use the original hole.