I don't think they suspended the investigation out of principle; the money was what it was "right after".
One of the attendees at that event was the Chinese billionaire Justin Sun. In 2023, the SEC brought civil fraud charges against Sun, alleging the unregistered sale of crypto securities, market manipulation, and deceptive practices, such as paying celebrities to promote tokens without disclosing their compensation. In January, Sun purchased $75 million of $TRUMP with 75 percent of the profits ($56.25 million) going directly to the Trump family. The next month, court documents showed that the SEC had agreed to pause the case as they engaged in talks with Sun to resolve the claims. In July, Sun announced his intention to purchase $100 million more of $TRUMP. Recently, he complained on social media that his $WLFI coins (a different coin sold by World Liberty Financial) had been unreasonably frozen, but then announced that he would be purchasing even more $WLFI tokens. His case remains pending, but there is no indication the SEC is actively pursuing it.
https://www.brennancenter.org/our-work/analysis-opinion/political-donors-should-not-be-above-law