Elia's Quest - Dragons (Campaign 3, Mission 4)

I personally played on Recruit difficulty, version 2.1. 183 dragons joined. And, by the way, it doesn't matter who goes to them – in my case, Railag followed them. Regarding reaching your own castle – it's not 3-4 days away; there's a portal right next to the dragons that leads directly to your castle, so that's not a problem.
And at the end, when the enemies see how many dragons you've acquired, they turn around and move to the left corner of the map, and there, the path to them is indeed 3 days long. But for some reason, they don't run away; they obediently wait for their fate in that dead end.