You do 90 day reports if you’ve done 90 days in Thailand (89 days after entry) or 90 days from your last report. If indeed yours is due on the 10th and you leave on the 9th then there is no issue.
Loads of posts like this. The answer is no you can’t, but some have done so.
Some embassies may require you to attend an interview at short notice, some may ask for a copy of all your passport pages and will see your latest entry stamp.
Whether you want to risk your application being denied is your call.
You do need insurance for a Non OA and for subsequent extensions from it. You don’t for a Non O. Any websites that you see that requirement are probably going back to the Covid era when it was mandatory. It isn’t now.