https://weathermodificationhistory.com/
see image of plane >>16326381 this is an old Beech 35 V tail built in 1957 there is a 'probe' sticking out the tail that is not standard on these planes.
Being single engine this 'probe' would be useless for air sampling as it is downstream from the contamination from the plane's exhaust system.
My best guess is it is an aerosol delivery nozzle.
It is quite likely that there is a tank in the rear seat space containing whatever it is that is being sprayed.
The system would be similar to that used by crop sprayers.
Think of all the shady airlines operated by the clown Air America etc.
Pay the pilots enough and they look the other way.
Pilots bribed and/or corrupted just like politicians to do the cabal bidding.