Windrose Technology, a Chinese-European startup, raised $400 million this year to develop a cutting-edge electric big rig aimed at challenging Tesla's new Semi truck. By March, however, the company had fallen into such disarray that its chief executive, Wen Han, was demanding to know where one of his $285,000 trucks had gone.

Two former employees fired in January, Travis Waite and Harold Keller, refused to help locate the vehicle until Han paid them a combined $91,000 in unpaid wages and benefits. They still have not been paid, they say, and the truck remains at large.

Han, a 36-year-old with a Stanford master's in business, disputed Waite and Keller's accounts and said the dollar amounts they claim are "unfounded."