Despite not posting new questions, jrdioko (the OP) visits the site from time to time and has even changed the accepted answer to one of their questions. So posting a CW with a summary of the country-specific answers seems very valid to me, and then commenting to the OP so they can accept the new one if they find it useful.
It could also be useful to talk to the user who posted the accepted answer, but they have not accessed the network for years now and that will probably be useless. Changing their answer in such a manner sounds a bit too much to me, also.
Once such CW has been posted, you can flag the one-line answers so they can be removed. Following what was commented in Juntemos en respuestas wiki las respuestas cortas específicas de regiones / Let's use community wiki to summarize set of short region specific answers, what we normally do is to convert them into a comment of the CW answer. Although it may look weird to have a comment with a timestamp way before the answer was posted, it is useful to track the information that was compiled in the CW.
