As someone that does some scouting that has been entertained at a high level, I'm going to gratuitously use the term "we" as a pronoun for the following sentence: We noticed.
Now I'll switch back to armchair GM mode...
They (see, it's not my fault) obviously thought that the goal scoring ability would prevail. And sometimes it does. Sometimes you can get more out of skating later depending on where you're at in the physical development arc. I didn't have MDC rated nearly as high as some, though my notes are on my home computer, so I can't say where exactly...but I don't recall having him in the top 15...even though I am very biased towards players that can put the puck away like he could/can...there were more than a few teams that did not have him ranked up here, but it only takes one...
Similarly, I didn't have Timo Meier ranked in my top 30...or even 50, if I remember right, in his draft year...the guy could barely stand up on the rink (speaking of Nikolaj Ehlers), he was not someone I would have been interested in taking even if I had three first round picks strewn about...but that's another guy where you take a look at the shot and you go "ok, well, let's see if we can fix the feet because the other guys we have in this tier, can't bury it from 35 feet"
You don't always win with those...as I expect we'll see with MDC and Meier...
But in sum, it's not that they didn't notice...they were just willing to overlook it - well, better way to put it is "look past it"...just like scouts looked past the lack of hockey sense of Jared Cowen, Dion Phaneuf and Luca Sbisa (for their size and handedness; slapshot and truculence; ummm...cool name...?)...various examples abound that I won't derail this MDC thread with...but it happens, they probably aren't gonna be right with MDC, but MDC still has the ability to make a fine living for himself for the next 12 years with the skill he does have...