If you made your save file before episode 15, you can get an azurill egg for a growlithe egg, if you made it in ep 15 you have a 1/18 chance to get it. You can return to reborn city after you finish all of the storyline through ep15.
This isn't really the place to ask this, but to answer: check behind the house in the bottom right for the chair and in the room you get to from the museum for the bookshelf.
1. You can go there after defeating the psychic gym leader
2. You need to go to spinel town to get anna some medicine
3. He is in the jasper ward trapped by a scolipede
You need to leave the city and head into ametrine mountain. From there you use dive (which you can get back at the circus from a puzzle) and find your way around the giant iceblock. From there go through the cave to ametrine city.
I wouldn't bet on it. We've already seen leaders using competitive items that we don't have access to, so I wouldn't be surprised if leaders got megas while we don't.
The FAQ page has been updated to say "If we don't decide to add a few new features, we might expect 14 in late October." So depending on how things go, we do have a tentative release time.