Earlier quoted context omitted.
I'd start with any one who decided not to ground the planes and deflected responsibility a soon as the first crash happened. They have direct responsibility over the second crash. The I'd go over all the certification process. Any person who concealed information or misled in an official capacity goes to jail. That's the whole point of requiring titled engineers signatures. The buck stops with them.
They were very likely assured by their program managers that the crash was a fluke, presented with convincing test data, and pressured by their bosses, the board, etc etc. These things rarely happen by individual malfeasance. They are part of a system of small mistaken assumptions that compound into big lies.
For doctors a failure can make their license get revoked (even tho it doesn't seem to happen very often in practice). Wonder if there could be something similar but indeed it is very hard to find "a person to blame", maybe the CEO? CTO? :)