Must didn’t announce any kind of contribution to Trump. Various left leaning social media figures ran this misinformation, however, I assume in an attempt to galvanize their side into donating and to continue their unhinged attacks on Musk.
https://www.wsj.com/politics/elections/elon-musk-has-said-he...
… and you might want to check with the source before saying he didn’t announce anything:
I guess you just ran your own misinformation.