This reminds me of my favourite story from Portugal which shows what happen when you hire someone for the sole reason that they speak English.
We were in Porto and stopped in at a small French restaurant for supper, which was relatively empty because it was off-season and early in the evening (for Portugal for supper. Really it was about 730). I noticed something off about the waiter immediately when he was walking over to greet us, as he had a weird wobble in his step, and a bunch of cuts on his face like he'd been in a fight or fallen, or something.
He takes our order, and then sort of stops and looks at us saying "Irish? No..." so we tell him where we're from and he then says in decent but accented English "Ah, Canada... did you know they.. invented a cure... for cancer? in Canada but the pharmaceutical companies, they buy it up so no one gets it?" and so on for about 3 or 4 minutes.
We're both fairly puzzled at this and I say "Uh, do you mean diabetes? I mean, I've heard that rumour, but it's not..." "Ah right! Diabetes! Yeah, the companies, they ..." and so on. At this point we realize that he's somewhat altered but he seems to remember what we ordered, so whatever.
He brings us the wine and proceeds to pour it from about a foot above the glass, just sort of generally aiming, and not really keeping his hand steady. I do the "hold the glass up to the wine" thing and somehow none gets spilled. As he turns to go away again and gets this knowing smile and says, "Canada?", as if he's just remembered a secret. We nod at him again, starting to realize what the deal is (high, drunk, or drunk and high), and he proceeds to go through the entire diabetes story again.
Later he comes back and says that the main I'd ordered isn't available (something with chestnuts, I forget what), but that they can make something else and put chestnuts on that. No, no, no, I'll just have the steak then, that's fine. "OK," he says. "... aren't you guys going to order wine?"
At this point, another group walks in, and after he seats them, we kind of keep an eye on them to see if they notice. even though they're not speaking English, the body language of "What the fuck?" is fairly unmistakable. Eventually we catch their eye and give them a big grin, at which point they start to sit back and enjoy the ride.
At one point, I made the mistake of asking him what soccer game was on the TV in the corner, which was coming in with slight fuzzy TV reception. He proceeded to grab the two aerials and randomly twist them, wherein I wanted to crawl in a hole and die, and the owner of the restaurant started to look like he wanted to throttle the waiter.
After he nearly dropped a dessert on us, the owner of the restaurant finally had enough and sent him to the back even though he didn't speak English. He actually knew what soccer game it was. :)