You made an analysis, wish you had made it to have more sense.
First & foremost thing you should've known is that Aaj Ki Party song has been choreographed & shot twice. There are 2 versions & both of them are not in the movie. So you're talking about a song becoming chartbuster & that song not being in the film at all.
P.S. - Salman Khan has only said that if the movie stays strong for 5 or 6 weeks then on public demand this song will be added to the movie end credits, but not the video song that's released. The one shot for the film is different.
SUBJECT & LYRICS
And this is supposed to be an EID song without the word EID or EID MUBARAK in it's lyrics. The only line that makes the reference is "chand ko bolo uthre falak se". Muslims can take it their way of waiting for the moon to appear. The ones who aren't muslims can take it the easier way of waiting for the night to happen because night time is the best time to party.
If you've any problem for "Dum Dum Dukur" or "Dhim Phata Phat Jhingri Papo"... You just haven't heard any old super fun songs of Kishore Kumar if you think this is the very first time something like this is used. It gets as old as you can imagine. Easier way is to try & remember one of the most famous Big B song.
SINGER but you also make a deliberate attempt at taking a hit on the buzz.
Straight away, this song is not in the film. So what good is the buzz if people don't find the song in the film? And regarding Mika, what's the fuzz? It's not like every Salman film has him singing for him. It's just 4 songs - Dhinka Chika (huge chartbuster - Ready) followed by Desi Beat (Bodyguard), Jumme Ki Raat (Kick) & now a song that's not part of the actual film.
Well this is what you get when you're 50 & a natural dancer, easily looking better compared to your colleagues of the same age while you dance.
Sets and Costumes
Right away, you haven't seen B Grade films.
And lastly, what makes you think Selfie Le Le is not popular? Think again.