If they were cooking the books why not show profit. What maters

"B. Riley reiterated $70 price target. Canaccord Genuity, maintaining buy rating and $69 price target
March 17, 2021
B. Riley Securities analyst Christopher Souther said he saw the selloff as a buying opportunity and the news did not change the historical or future growth trajectory of Plug Power.

Souther, who reiterated his buy rating and $70 price target, said this is "another piece of accounting noise that has created an additional buying opportunity in the stock."
https://www.thestreet.com/investing/plug-power-tumbles-as-analysts-split-on-accounting-error-impact