Why wasn't Rumble elligible for the new Conqueror skin line?

So, yesterday we got to see a sneak peek of the new Karma skin, which is now supposed to be the new skin line celebrating esports, being a sort of revamp of Challenger skin line.

And now from what I understood, the champion picked for this skin line is supposed to represent their effectiveness in the past few months and be a sort of coming up MSI event promotion.

Now the question is, why wasn't it Rumble? He's seen a pretty noticeable spike in playrate, this time both in competetive AND soloq (he's seen a pretty consistent 7% pick rate for past several months or so, pretty impressive for a champ who used to have 12% at best for years), he's been recognized by playerbase, and most importantly, he was a really effective pick, and it's still looking like he's gonna be one. Why not make use of Rumble's... "renaissance" if you will, take advantage of it and give him a skin? Especially considering how he's been kinda left out in this regard, meanwhile Karma has gotten a lot of good quality skins + some really great new splash arts (and on top of that her last skin was released in last december or so, giving us barely 5 months of downtime before she's got a new skin).