Patty - I messaged you. I would take Tucker to the Cat Emergency Room/Vet.
This could be a simple grass eating incident or something worse.
You said he vomited grass. What if he ate something poisonous outside - rat poison, poisoned rat, or something similar. What if something bit him - poisonous spider, similar.
Theresa and I have a big regret. We lost Scoobs (non-diabetic) in July 2016. Apparently fine the day before. Then 10-12 vomits over 12 hours until bloody vomit. He died from necrotized intestines. Could have been cancer, could have been poison. Instead of the emergency room we had him at the regular vet for 2 overnights, then the surgery. In retrospect I would have treated the whole deal as an emergency and paid the emergency clinic for rapid care. We will never know if emergency services could have resolved the issue.
There is the low possibility of side effects from the very low BG incident - just 4 nights ago. I think these issues would have manifested by now. However, if some cells or portion of an organ were damaged from lack of glucose, this should be considered by the vet.