If the consequence of violating a law is a fine, that law is essentially optional for the rich; if the consequences of violating a law is prison time, but the penalties can be avoided through (expensive) legal protection, those laws are also optional for the rich. The rich are hard to prosecute under the law, so it’s not surprising when the law is primarily enforced on the rest of us (esp. on the most vulnerable of us).
An easy example: the IRS audits the poor much more than the wealthy, partially because their attempts to target the wealthy was met with legal difficulties.
Looks like the DOJ did send a letter:
https://www.vanityfair.com/news/story/elon-musk-doj-letter-paying-people-to-vote-is-a-crime