here’s a quote from that article:
“With regards to the exact date and time of Rabbi’s Weil’s ‘petira’, Mr David Seldner contends that there are differences between the local council’s version and the universally accepted version. The date on the Korban Netanel’s tombstone is 7.5.1769, which was on a Sunday (30 Nisan 5529, Erev Rosh Chodesh Iyar). However, according to Jewish sources, he was niftar 15 Iyar 5529, which was the 22 May 1769 and was on a Monday. To compound matters further, it is a well-known historical fact that Erev Shabbos was the day he was niftar. In fact, the levaya was attended by many gentiles, who regarded him as their ‘wunder-rabiner’.”