'...I went to the hospital from eating a tomato turkey sandwich non-gmo spinach pizza etc. So no tomatoes for me...'
How do you know it wasn't the bread? Or the turkey? An ingredient in the turkey if it were partially or wholly cured?
'...Should I be concerned and is that heart damage permanent?...' The elevated troponin is a marker of some kind of myocyte damage, but it's a low result. I had the same after going into AF and having a cardioversion (four in total and none of them worked more than about 10 hours). The heart damage is only permanent if tissue dies, such as during a heart attack. Otherwise, like all living tissues, they can repair themselves, at least partially. Your troponin levels will almost certainly be elevated after your upcoming ablation as well. It's natural. After a couple of weeks, as the heart calms and repairs what it can, those levels should return to a low.
Being lightheaded at any time when you have a formal diagnosis of an arrhythmia could be the arrhythmia returning, it could be bradycardia when in normal sinus rhythm (NSR) caused by metoprolol or another rate control medication (you've stopped the medication), or it could be a temporary hypotension and syncope caused by sudden movement or standing, perhaps by dysautonomia. This is only a series of guesses, not a diagnosis as I am not qualified to make such a diagnosis, nor do I have access to your records.