For those of us whose events (on their Google calendar) are not showing up on our web Google calendar, I figured out a crude workaround. It's not a full solution, but at least it helps.
1. Log into your Google calendar on your computer.
2. Open your Samsung calendar app on your phone. Deselect all calendars but the corresponding Google calendar.
3. Compare the 2 calendars and check to see which events are missing from the computer. It may be helpful to do this in agenda mode.
4. On your phone, open an event. Hit the menu button, then hit copy. Make no changes. Save the new event.
5. Back out of this event. You should now see a duplicate event. Hit the menu button, then hit sync.
6. When it's done syncing, reload your computer's browser page with Google calendar. You
should see your event, finally on your computer browser.
7. If it worked, go ahead and copy each event, 1 by 1, on your phone. Once you've done them all, sync. Check the browser to make sure you got them all.
8. If you're really lucky, it will somehow update both events and you can delete the extras on the browser. If you're not, go ahead and delete the
first event of each pair. I recommend you sync after each delete to make sure you got the right one. It would really suck if you deleted a bunch of new events and had to do it all over again.
Well, that's it. Hope this helps some of you. And, hope you don't have
too many events to copy

If anyone finds a better workaround, please post it here.