I'm almost certain this didn't happen (and as you know, I'm decidedly not a Trump fan).

His only rally that day was in St. Cloud, and the speech is online. I'm not going to sit through ninety minutes (or even ninety seconds) of him speaking, but searching the transcript, he only mentions btc briefly when talking about his day, noting that he went from talking to evangelicals to talking to bitcoiners, talking about how broadly his campaign was focusing.