I don't think there's too much to read into here. Of course Alf and Raiola are going to meet with Barca. And Madrid. And PSG, and Chelsea, and United, and every other feasible club in the world. Why wouldn't they? It would be criminal negligence not to! See what they have to offer, negotiate, use that in other negotiations, and source as many "best" offers as you absolutely can. That's how this works.
I'm sure Erling himself even has some level of interest in most of these clubs. What footballer wouldn't?
The fact remains that no other club can offer the financial package (for the player and Dortmund), has a glaring need for a striker in his vein, a strong supporting squad with the ability to win trophies, and a second to none manager, coaching staff, and supporting infrastructure. Oh and the cherry on top is his dad played for the club and he clearly has some level of affinity for us.
His representatives will meet with every club under the sun, very publicly. They will drive a hard bargain. That is their job. But no club makes more sense for Erling then City - on so many levels - and this might be hubris on my part but I'd be very surprised if he doesn't end up here.