> The longest the bulb remains stationary and lit is about three seconds in the video. <
That’s the key point right. It’s not obvious, but the guy is the external power source here. His stored muscle energy is being converted to light energy. No free lunch.
All well and good, but where's the motion, the prime mover force (and energy) here?
I believe what is happening here is an oscillation between the strong magnetic field from the permanent magnets and a current (and field) generated in the coils. Just as you can set up an oscillation between an inductor (coil) and capacitor - tuning a simple AM circuit to make a crystal radio... Conductors and magnetic fields can oscillate.
The initial energy for the system comes from moving the coils on the ends of the florescent tube into the strong magnetic field. This sets up a current, creating a counter field that pushes back. The coil/tube/magnets oscillate - but the system is losing energy to losses in the wires (tiny) and to energy pulled off within the tube and converted to light.
I'll bet you the light would flicker and die within a couple of seconds without more energy being added to the system in the form of moving the coils through the field.