Hi @fclifton,
When testing with the All day event, I got the same issue with you.
Then I tried to convert the timezone from UTC to Pacific Standard time using the ConvertTimeZone function.
First, using the Compose action to convert time with the following code:
converttimezone(triggerBody()?['End'],'UTC','Pacific standard time')
Second, in the Google calendar action Create an event, enter the following code for the End time field:
formatDateTime(actionOutputs('Compose'),'yyyy-MM-ddT00:00:00.0000000+00:00')

When an All day event is created in Outlook calendar, it will be created on the Google calendar without issue.
Please have a try with it on your side.
Best regards,
Mabel Mao