How long were the Chilean miners trapped? It took months if I recall for the best drillers in the world to get to them.
Considering the type of cave (small narrow passages) and the annual precip in that region and that its monsoon season, I’d say the rescuers have been doing pretty good. They might be able to drill for them, but there is as likely a chance that by drilling that they collapse the very cave they are taking refuge in. The earth may not be as stable as the deep bedrock the Chilean miners were buried under.
Thailand, as you note, is not a wealthy country. But they are not in the $h1th0le category either.
69 days. One of the men said, upon being freed, "That was a long shift."