If you can get it all properly timed up again, take the plugs out the rocker cover off and turn the crankshaft very slowly by hand. It it turns over reasonably well, looks and feels consistent, you might not have done any damage. Do it again and again. And again..... Check each rocker / valve individually for function and visual consistency. At the slightest sticking stop. Note which cylinder caused it in case you need to take the head off. Get a compression test done anyway. Only once you are sure it's OK and the compression is consistent across the 4 pots AND HOLDS the pressure consistently across all four pots for at least 30 seconds, should you be even slightly satisfied you've not trashed it.
Even then, I'd still be reluctant to turn the key. I'd just have the head off and check it all properly, replacing the chain and cam gears as well.
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