Hello,
I can reproduce the problem. The (a) problematic event is
BEGIN:VEVENT
DTSTART;VALUE=DATE:20170820
DTEND;VALUE=DATE:20170821
EXDATE;VALUE=DATE:20180415
EXDATE;VALUE=DATE:20181216
EXDATE;VALUE=DATE:20190120
EXDATE;VALUE=DATE:20190818
RDATE;VALUE=DATE:20170916,20171014,20171118,20171216,20180120,20180217,2018
0317,20180519,20180616,20180714,20180818,20180915,20181020,20181117,2019021
6
RRULE:FREQ=MONTHLY;BYDAY=3SU
UID:a6p98i2kp66mg5e5ep6t2ot96g@google.com
…
This is an event without end (no COUNT or UNTIL in RRULE), and it seems that the existence of RDATE/EXDATE in such events can’t be processed by the Android calendar provider, which sends:
icsx5 : Found VEVENT: a6p98i2kp66mg5e5ep6t2ot96g@google.com
icsx5 : a6p98i2kp66mg5e5ep6t2ot96g@google.com not in local calendar, adding
RecurrenceProcessor: DateException with r=FREQ=MONTHLY;WKST=MO;BYDAY=3SU rangeStart=135390560256 rangeEnd=9223372036854775807
CalendarProvider2: Could not calculate last date.
CalendarProvider2: com.android.calendarcommon2.DateException: No range end provided for a recurrence that has no UNTIL or COUNT.
CalendarProvider2: at com.android.calendarcommon2.RecurrenceProcessor.expand(RecurrenceProcessor.java:768)
CalendarProvider2: at com.android.calendarcommon2.RecurrenceProcessor.expand(RecurrenceProcessor.java:663)
So, it seems that such events are not supported by Android.