The wiring is poorly terminated but it doesn't look loose...
There are no resistors required for compatible panels/inputs.
You shouldn't mix G3 Aux Fault and Aux Tampers together, but it doesn't seem to have been wired it like that anyway.
You haven't terminated the test terminal at the panel from what I see, so it's not doing the G3 periodic testing which I expected to be part of the issue.
I'd say it's DIY so just follow the instructions for Grade 2 installation using 5 wires. Make sure the bell hold off and battery works see if the fault clears.