I live in a country that has many more divers who aren't certified diving than certified divers. At the same time we have one of the highest death/accident/injury rates in the world compared with the general and diving population. The non-certified divers learned from their diving "cousin, uncle, neighbor, etc." and they almost all get hurt and have some sort of physical disability with neurological deficits. I once walked into a gathering place for commercial divers' hangout who were all non-certified and use Scuba for spearfishing. ALL of them had physical issues and practically all of them were limping one way or another. Of course, no one can teach them anything since they "know it all." I couldn't believe the shiit they did while diving and the extent of their ignorance and the "fairy tales" they believed as the "truth."
It is isn't about "certification" but more about "proper training." Have your friend find a good instructor who actually "educates" the students and gives them time and effort to get trained properly and also get certified. And as it was said above, if they can't afford to do the training, they have no business getting into diving for the training is the least expensive part of the process.