I checked 10 GMB pages and only saw 1 with a spike that week.
I personally think there are many discrepancies in those stats. Google webmaster tools stats are often garbage as well.
Or sometimes google will move a website into top positions for a short period of time to measurement click through rates, time on site, and other engagement metrics. If those metrics aren't better than those sites normally in top position - then google will move it back out of top results. This could also explain the spike.
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