No, no, and yes. On a similar note, I spawned a bunch of chickens in a 1x1 area over a hopper and surrounded by glass in the Nether, exactly where the bugged ones had escaped. Later, after traveling to the Overworld and back to the Nether multiple times, I check on the farm to find the area completely empty where I had previously spawned at least 100 chickens or so. Sometimes a few would bug out of the farm due to lots of entities being in one spot, but it never completely freed them all at once. Later I did find a few that had gone through the portal, but that was it.
No, no, and yes. On a similar note, I spawned a bunch of chickens in a 1x1 area over a hopper and surrounded by glass in the Nether, exactly where the bugged ones had escaped. Later, after traveling to the Overworld and back to the Nether multiple times, I check on the farm to find the area completely empty where I had previously spawned at least 100 chickens or so. Sometimes a few would bug out of the farm due to lots of entities being in one spot, but it never completely freed them all at once. Later I did find a few that had gone through the portal, but that was it.