All German tanks used gasoline engines, that includes MKI,MKII,MKIII,MKIV, Panther and Tiger, none used diesel engines. True, the T34 suspension was based on the Christie design but it wasn’t designed by Christie or any other American, it was modified and adapted y the Soviets for the T34 design. It was also used in the BT light tank series.
The Germans didn't produce diesel-powered tanks during the WWII in quantity. Neither the Tiger, nor the Panther, nor the previous models were diesel-powered. Actually, their diesel manufacturing worked for the submarine fleet.
Christie suspension was designed by an American
The Christie suspension was really designed by an American, and the USSR bought a licence for this, but the technology was neglected by the American industry, while the USSR has developed it further.
Another reason of the T-34 success was innovative using of assembly-line automatic welding systems, invented by professor Evgeny Oscarovich Paton. It allowed large output while being in shortage of skilled workforce.
I think the soviets should get some credit but they do have a history.
Of course, like everyone else.