I can confirm it, I have had this same problem after I updated WA with the patch right before Ambitions.
After Loft Stuff, my EADM borked and I did not bother to patch the game manually... however I did not have any problem with playing an earlier WA (i also managed to catching the red assassin bugs in china required for a mission, you just have to zoom and wait them to crawl out of the soil).
After ambitions I patched my game fully, and the excavation sites stopped working for a problem with pathfinding.
A related problem: in China it has become difficult to get on the slope rich of metals behind the terracotta army, not impossible, just difficult (you have to route your sim manually).
The only relic sites working are the ones planted right inside lots and tombs.
(There are many still working in Egypt, one at the Queen's temple, three at the copper mine, and in France there is one at the ancient celtic tomb).