I don't know what sources you're looking at, all the ones I could find say the 30th:
- White House press release: https://www.whitehouse.gov/briefings-statements/remarks-pres...
- Reuters: https://www.reuters.com/article/us-health-china-usa-trump/tr...
- Politico: https://www.politico.com/news/2020/01/30/trump-close-coopera...
- Vox: https://www.vox.com/2020/4/17/21225010/trump-who-attacks-cor...
- ABC News: https://abcnews.go.com/Health/wireStory/wary-irking-china-tr...
- Al Jazeera America: https://www.aljazeera.com/news/2020/01/cloneofcloneofcloneof...
This wasn't difficult, I just searched "Trump coronavirus very little problem" in Google News to get a vague idea, then limited it by date to get more specific results.
I couldn't find any evidence whatsoever for it happening on the 24th. To publish it on the 24th would require either time travel or some insight into planned speeches.
It kinda feels like you're trying to discredit Der Spiegel for some reason.