Any chance the area being referenced in relation to Germany is near the headquarters of a company named aaronia? They manufacture, high-end spectrum rf analyzers, and high-end drone tracking and jamming/drone disabling equipment.
(As a result, I would expect them to be testing, and or demonstrating their equipment near their headquarters.)
Just a guess/speculation as I’m familiar with aaronia’s products and services (indirectly)
If any civilian company jammed GPS enough to affect commercial aviation that would be a huge no-no - RF emissions in places like Germany are strictly controlled, even if you're just 'testing'