An opinion, which carries absolutely no legal weight at all, and quite frankly isn't even grounded in the law...
The Song is most certainly copyright by somebody, very likely Cedar Fair, L. P. or possibly the composer. Copyright protection exists upon the creation of the work, and that song is recent enough that such protection would still exist.
Technically, any redistribution of the song without permission of the copyright holder is probably illegal (I say "probably" because I'm not entirely familiar with fair use provisions).
That said, there are a couple of potentially mitigating factors here. One is that the distribution we are talking about here is a noncommercial distribution which might possibly be covered under the fair use doctrine. That may be a stretch. Second, the song in question is clearly a marketing device, and insomuch as its distribution is promotion for Cedar Point, it's unlikely that Cedar Fair would actually object.
Furthermore, if Cedar Fair does object, we know their representatives monitor this discussion group, the "offender" is personally known to them, is easy to contact, and will probably comply with any request to cease distribution. I'd think that if it was a problem, the file would be gone by now...
--Dave Althoff, Jr.