Not wanting to bang on about this, but I just think it's wise to be careful.
Korea was one of the races that James Allen didn't attend. He is largely relying on the exact same team post-race press releases as we all are.
That article would be before any pre-race team conference calls, most team engineers would still be flying home or flying somewhere between Korea and India.
The article is composed of an FIA press release, an article from AMuS, and I would suggest (especially the terminology used) the McLaren press release.
All nicely recomposed and paragraphed and all that. All very loose and conversational, and in this case I would argue there is enough elbow room in the language used to suggest that 'some' may not necessarily have to be used plurally, it could mean one.
... I guess I am not so much talking about blocked-up McLaren front wings anymore, but probably wandering into the problem of unsourced articles. It could perfectly well be referring to the exact same press release we were talking about, so not double-sourcing or independently confirming, it's just the same source retyped.
If someone else goes on record saying marbles have been clogging up their front wings, and maybe they will this week if asked, then clearly argument over, but right now we've only heard this once, from one team, in one race, and in circumstances that make the story seem somewhat unlikely.