Except Cynthia doesnt send out Spiritomb before Garchomp. It's always Garchomp in the anime, manga, so on and so forth. She only ever really leads with spiritomb in champion battles but that's outright contradicted in every single other form of media, which last I checked, we use. In a random encounter? It's gonna be Garchomp, because it always is.
You're also ignoring that they start off close to each other, unless you're arguing Cynthia starts out with her Pokemon, which she doesnt because that isnt how summoners work, or the fact her Pokemon, while she uses them, arent her and thus arent apart of the SBA range. Otherwise you may as well argue Cynthia has infinite range with her Pokemon because she can tell them to go however far she needs to.
And as for hitting soul energy.
everytime a ghost Pokemon doesnt want to be seen or touched, it isnt seen or touched. Ghost Pokemon have like two different states of being, an invisible, intangible state and one that can be seen and touched (although sometimes it's still intangible if it chooses). Going off the numerous times that's shown in the anime, with Gengar mostly. And I've never seen a ghost pokemon get harmed or even seen by someone while in their former state. Only in the latter, in fact I've seen Ghost Pokemon abuse their intangibility to phase through attacks.
If you want I can go compile a bunch of instances and make a CRT for it, if we use anime and manga for Pokemon we gotta consider the fact that, the anime (especially) and manga tend to have ghost pokemon having two states of being.
You're also ignoring it's in character, Cynthia doesnt kill, SBA says she's willing to kill, as are all characters but that's an absolute last resort, she aint gonna try to kill what she assumes to be an average man. Hell she may not even take him seriously.
Not to mention Kira doesnt have to blow up 108 souls to kill Spiritomb, Spiritomb is made up of 108 souls, but that's the thing, it's made up of, as in all those souls form together to make one being. As such no, Kira doesnt have to blow up every single individiual soul as all those sols came together to form one being, they're one now. Actually, qouting the Pokedex, this pokemon was formed by 108 spirits. Formed, as in 108 combined to make one. Given they're now what constitues as one object, Kira's one object at a time rule for #1 is a non-issue.
idk Cal but you're being kinda dishonest, you're ignoring the fact Cynthia doesnt kill, the fact she'd only actually send out one pokemon initially, the fact that in every single media other than sanctioned tournament battles she has always lead with Garchomp (and tbh im pretty sure she's lead with Garchomp in one anyway elsewhere) in every single instance I can think of, whether that be in the multitude of anime episodes she's in or the multiple manga, that Kira and Cynthia really arent that far apart and as such Kira having bad range really aint much of a issue, the whole Cynthia has to actually call out the pokemon first which isnt exactly the fastest of things to do and because you wanna debate that, the fact that Ghost Pokemon, from what I can tell given all the episodes and manga ive read, have never been hit when in their noncorporal state.
