If giant cats and amber mountains existed somewhere in the universe, then perhaps they could generate lightning.😁

Speaking scientifically; there is a similar cause for the amber/cat fur electricity and lightning, both are the result of the separation of electrons from atoms by the attraction and motion of opposing charges.

The premise is that everything that happens must have a cause.
The TGFs occur in the Earth’s atmosphere, what causes them is unclear.

It is a fact that radioactive atoms give off gamma rays.
Is there a connection between radioactive atoms and TGFs ?
One way to find out is to flood the upper atmosphere with radioactive atoms and see if the TGF count increases, 😉 I do not recommend this procedure because the consequences could be devastating.
Another way might be to see if the TGF count and the radioactive atom count in the upper atmosphere has increased over the years.💡
If there is several years worth of data to indicate that there has been no change in either count, then that could indicate a stable condition of still unknown cause.

Scientific or not, those are my thoughts.😁