Even that link lists it as a double a-side single, "TBA/The Matenrou Show". Tsunku wrote on his blog that he finished TMS long before OTT, because he kept rewriting and changin OTT so it would match the image he wanted, hence the TBA.
That pachinko video is not a PV. I mean, it looks cheap even for Hello!Project standards But the pachinko thing is an ongoing tie-in since the release (the CD has a sticker with it), I can see why they re-recorded it with Risa who just left the group at that time. Only members who are over 18 can appear in it, so they couldn't include anyone but Sayu and Reina. Sure, they could have used Sayu but I remember people saying that "Oh this song would have been soooo good with Risa and Ai". Well, you want to hear the song with Risa in it? Go play pachinko. And then maybe buy the single after that if you like the song.
I don't think they ever planned a TMS pv. The single is a double a-side, but that doesn't mean anything in Tsunkuland . The Peace had Dekkai Uchuu de... listed as a coupling track on the cover, but it ended up on their next album and even had an instrumental version (plus, it was on both Best Morning Musume 2 and the coupling song collection.. it's all very confusing ). Kono Chikyuu... had Kare to Issho ni... listed as a double a-side and it even had a PV, but I think that was only because they wanted to show the fans that the group won't be over after Ai leaves, Reina and Sayu can take over the main vocals/centers (remember, Risa's graduation was planned at that time as she wanted to leave with Ai but the management asked her to stay a little longer). So yeah, TMS will be on the next album/the future best albums and we have a dance shot, that's all. But it's better than nothing.
Sorry for the long post and the bad English but I just had to say it