I have no major issues with iPhones generally speaking, but jailbroken iPhones don't behave the same way. In my experience updating a phone which was previously jailbroken is not something one would be doing anyway, so it seems you do not know much about jailbroken iphones.
As such, there is unlikely to be a forum to resolve your challenges. There are forums, and I have fixed many iPhones with the use of Google, but it can be a time and resource intensive situation. Given that you may have already bricked these devices by trying to update them, perhaps you would be better off buying a modern phone and not attempting to jailbreak it! You do not appear to have the right skills, or you wouldn't be asking on BHW how to fix this type of mistake.
If you are state-side, you could mail the iPhones to me, and I would try to repair them. I cannot make any guarantees as I already said ... there is a chance you already bricked the phones, but there is also a high probability the issues can be resolved.