Touch it and pay!

MEX is N/A, so you have Asia-N/A-S/A-Eur-Asia

So it's a DONE4.

FWIW, there are no xONE3 fares published for S/A, Africa or SWP origins as no defined routing avoids any of N/A, Europe or Asia.

Even possible exceptions are excluded, for example direct travel between ORD and DEL is specifically noted in the rules as effectively touching Europe.