Because all the airliners are the same graphic, but are correctly identified and not actually being described as 707s (Wikipedia tells me the remaining 707s are mostly business and cargo planes and not for passenger travel), I'm assuming it's just whatever stock graphics were available... That would seem to imply they haven't updated their stock graphic inventory for vector graphic airplanes in almost 20 years, but it's not really that unusual when you're talking about something less than 1% of your audience is going to pick up on.
The major cable news networks in the US regularly get caught doing stuff like this. It wasn't that long ago that every story about a fighter plane was accompanied by a picture of an F-14 and every story about an assault rifle was accompanied by an AK-47. Now, they're slightly better at things, but they constantly get caught just using whatever the first Google image search result for a thing is without clicking through and seeing if it's actually the right thing, and that's really no different than slapping whatever stock graphic you have in the top drawer on everything.
To indulge the theory for a moment, an EF-111 couldn't have shot down the MH17 at all. The best it could have done is maybe save the plane, but I don't know what it's capabilities actually are, except that no coalition plane in Desert Storm was hit with a surface to air missile while one was on station, so it was apparently pretty good at its job.