You make a good point. Unfortunately, there's no way of knowing in this case. It's probably a mix given the high rate of errors. The analogy I would draw (probably a poor one... analogies are not my strong suit) is that a mechanic may be able to fix any type of car, but they often have specialties. If you have a BMW you'll want to take it to a mechanic that specializes in BMWs. They may not be able to fix
every type of car as well as they would be able to fix a BMW, but they'll do a better job on the BMW than the general mechanic would. Such is MD/pharmD. MD can do a great job with meds, but in the end the pharmD will know better
with respect to the meds. It's an imperfect analogy, but you get the idea. You can also look at it from the other perspective and say that a pharmD can look at the meds, but they generally don't have the background to diagnose and look at other possible treatment options outside of the meds.
Either way -- knowledge-related mistake or slip of the pen -- a mistake is a mistake (especially when 92% of the cases had some sort of error... no way is 100% of that oopsies or 100% of that lack of drug knowledge) and it's good to have a safety net in place and be able to acknowledge it. MDs, nurses, pharmDs, etc. are not infallible.
The more we collaborate, the better the results will be... other than that collaboration takes extra time and discussion

. In a perfect world we'd work based on quality of care and not quantity, but at the end of the day the big guys are focused on at least breaking even, if not making a profit.