I haven't been able to get the boot file that you linked initially and I thought it was expired. It was my PC security that was blocking access though. I have since downloaded on my phone, copied to PC and rooted the phone. No bootloop.I attached image to my previous post. But instructions are also in this thread. Pay attention not only to numbers 30b, but also to security patch date. As you can see it is different for different LG G7 phones.
They must be the same, otherwise you will get bootloop.
Thank you for your reply.