Except if you bypassed payment and used the service in a manner that was not intended, most likely you were by definition not undertaking "strict adherance" to service terms ?
For all intents and purposes it is the country of registration of the aircraft.
There are one or two exceptions to the rule, but they would not be applicable in this scenario. Mostly stuff relating to air safety. For example, if the aircraft did something against the aviaition laws of the country being overflown. Or hijackings etc.
IIRC the way it works is that when you land (destination or forced landing elsewhere) the offender is delivered to the local competent authorities.
They then undertake an initial investigation and decide either to exercise their own jurisdiction or undertake extradition proceedings to send the offender to the country of registration of the aircraft.
In a scenario of (attempted)murder, I suspect that it is highly likely it would be dealt with in the local courts unless there was a specific external push for extradition.
The point of the convention is to ensure there is never no jurisdiction, i.e. the country of registration to the aircraft is always there as the ultimate fallback. The wording doesn't seek to strictly define the jurisdiction, which is why in most cases the delivery country has the option to take jurisdiction.