The E.R. Doctor might have had a question or two! I am surprised that the cans did not explode. I don't think I would have the courage to try 30 year old cabbage... fresh cabbage does me in (or out)!
I ate of it out of several cans over a period of months, and did have friends sample it.
Canned foods don’t make you sick, they can only change in flavor and quality and nutrition, but they are still safe to eat, with only the normal canned food rules applying, in other words, as long as the can is still sealed and not bulging, eat it.