Hello, sir.
My name is Alexander. I'm Ruby/RoR developer from Ukraine.
My main direction is Redmine plugins development so I know Redmine well.
I didn't facing problem like this but I have some thoughts how we can remove it.
Honestly - I can not give a 100% guarantee that I can fix it. To do this, we need to carefully examine what exactly is the problem.
If you choose me, I will not turn timer on, so you will be able to reward me as much as you want.
Although my usual hourly rate is $10
With respect,
Alexander