I play every game mod or not with an ad blocker. It does help a bit, but ads should not be causing an instant crash.
If this was happening to my game and device, I would backup everything and do a full complete restore.
Before restoring, please test your internet speed. I’d hate for you to go through the process of setting up your phone like it is right out of the box if it is an inernet speed or bandwidth thing.
Running a virus scanning app would be a good idea.
complete restores are a pain and a very last resort.
Start with testing your phone’s speed on your internet connection.
Test for viruses
With your phone not being Jailbroken and running a version of iOS that is hit and miss with some people with iPhone 6, issues can happen.
I can use a Cydia Impactor in any app except this one and I do not have a test account. It is a Dev account. Yet there is always a solution.
For example: My wife’s phone was glitchy with certain apps while running 10.3.3 on her iPhone 6.
My friend had no issues with his iPhone 6 or my IPad 4. My iPhone 5 was buggy with 10.3.3.
The problem could be with how your specific device is communicating with it’s os even if other people have the same phone and no issues.
Only upgrade your iOS if a system restore did not work. 10.3.3 is something to keep on your phone. If it is not the problem a higher OS could trigger a different set of problems.
Keep me posted and I will try to simulate your game issue another way.