Sorry if this has been discussed before...
I think you're probably safe. There's not too many people that would make this particular assertion.
Furthermore, I don't think it even qualifies as a coincidence. The most popular date for the "end" (which it wasn't, really) of the mayan calendar is Dec. 21 2012, so I don't see how that very specific date relates to something that happened a month and a half prior. In addition to this, if you'd bothered to follow the link referenced on the jwfacts site you would've seen that the date refers not to when this change occurred but to when the article summarizing the annual meeting was published online. The change became official JW doctrine when it was announced at the annual meeting in October. So one event happened nearly 3 months prior to the other.
Given that nothing actually happened on Dec. 21 2012 makes your assertion of some connection all the more irrelevant.
I don't know why I'm bothering with this. I just always find it profoundly irritating when people try to make something out of nothing like this.