Is there for it any proof except the appearance?

The official material and also the Games itself speak against it.

If I remember correctly, you ride a tram to the turntable area in both Re0 and Re2 (Coming from different directions). Who knows how long those tram rides are? We don't get to see the whole thing. The one in Re0 could go all the way from the forest to Raccoon City.

Yep.

Also the games don't speak against it, you are looking too much into things, and as we all know nothing in Resident Evil should have alot of thought into it.

The tram can not far take away from the trainings Facility.

After the journey with the tram one explores the factory, the lab and, (above all), the Treatment plant. As see which Rebecca and Billy after her escape from the exploding pant are also in the woods near of the mansion from RE1.

Rebecca meets Enrico in the lab. Enrico says that the mansion (from RE1) Enrico says that the Mansion (from RE1) is nearby.

Nevertheless, according to Weskers report II and the RE book Birkins lab lies directly under Raccoon city.

According to the passenger diary (RE0 file) the area the training Facility 8 miles of RC lies away.

If it is really only 1 lab how Billy and Rebecca came then in the RE0-Ending again to the woods? Have Rebecca & Billy run after the final battle 8 miles of RC back in the woods?

The "magic elevator" is a gameplay mechanic. The lab isn't directly under the training facility.



We don't know how far away they ran. And if anything, it was a fair distance as there is a mountain seperating the training facility from the mansion. They are quite far a part. Even from where they were standing, it is still quite a walk.



The Treatment Facility is quite large, and they travelled the whole way through it. Not only that, the long ass elevator goes up at 45 degrees angle, placing them even FURTHER away by the end of the game.



Neither of them do. Birkin's lab lies directly underneath the OUTSKIRTS of the city (hence Sherry's statement in RE2). The factory disguise of the laboratory is located in the industrial block of the city.



No he doesn't. He says that they should "end up" at the mansion.

Not for the first time, and worryingly, not for the last, Capcom cause us suffering at the hands of lazy development ~ and it is lazy, becasue it would have taken minimal effort to have matched up the geographical locations. So while Prime Evil is logicaly correct, the conclusion is fated to be errornous, not by his/her misjudgement, but becasue of Capcom's failing ~ They are the same place, the story dictates this, it's a cross-refrenced location for the games geography to apparantly match up, and is partially evidenced by the in-game cut-scene with Wesker & Birkin discussing their final plans for the facility.