My apologies. I didn't see your last reply before!
I checked https://www.google.com/calendar/ical/43djdemn16t5o5tn701j900ii4%40group.calendar.google.com/public/basic.ics again and I see these timezone-related settings at the top:
X-WR-CALNAME:Finding Yoga classes and events
Next I looked for an event that could be listed on Jan 9, and I found this one:
LOCATION:Sun Salute Yoga
SUMMARY:Gentle Yoga for Persistent Pain
I'm not sure if that's the even you saw listed in your widget or not, but it has some complex rules, and I bet you could fix the problem with the Jan 9 event in the short term by finding the older one from 2013 with the title "Gentle Yoga for Persistent Pain" and removing it.
I also checked for an even on Jan 16, and I found the same title, "Gentle Yoga for Persistent Pain." Could you try searching for events with the title "Gentle Yoga for Persistent Pain" and removing that one recurring event from the past in your calendar since it seems to be causing some odd problems?
Were those events on Jan 9 and 16 the only remaining problems left?