> Hindenburgresearch is a known short-seller and so has an self interest to drive down the stock price of Nikola.

Short sellers don’t really have an interest to lie though. If it doesn’t look like there is really a fire, it’s much better to close the position and hunt for a new target rather than trying to make it seem like a problem when there isn’t. Lies don’t help short sellers because they present a legal risk and a financial risk (the market steam rolling them as they are seen through).