Back to basics.
1. The inverter
output must have a neutral to ground bond.
2. The genset must have a neutral to ground bond at its output.
3. The inverter
case must be tied to the vessel ground with a conductor the same size as the B+ feed or one size smaller.
4. The shore power safety
green (grounding) conductor is tied to the shield between the primary and secondary windings of the isolation transformer, not the case.
So far your installation
appears to be unconventional but all the boxes are checked.
However, before any more help can be provided; what is the model number? A quick Google
of AIMS shows that Amazon has an AIMS inverter/charger
listed. Is your unit an inverter/charger as this changes things quite a bit?