Why doesn't World match the Dungeons from the outside

Good example would be Wanders Palace & Turn 6. The layout of these dungeons doesn't match what they look like outside of the game. Could SE please explain why they didn't just make the dungeon look like what it should look like from the outside.

Wanders Palace doesn't have walkway to the tower from the outside.
Turn 6 from North shroud doesn't even come close in distance/tower design/floating rock from the outside.

SE has designed content 6+ months ahead (In terms of models & layout) and they couldn't do this..?

I know this is just a game but iv seen other games do a better job to actually match what it looks like from the outside.

Honestly, in scale of geography and relation to what things would be like from the outside, I think they've done a marvelous job with keeping things as true to scale as possible.

Wanderer's Palace, for instance, winds upwards. You embark from Bronze Lake, coming up to the 'front' of the dungeon and then get up into the first level you start in. Winding your way upwards a little with the first set of stairs you come to, while going further into the 'back' of the Palace. Basically fighting in a courtyard in what would be the middle. From the second part, you work your way upward and downwards 5 flights of stairs. Specifically, up 2 small, up one long, down one long, up 3 small, down one small into the final chamber. So this 'tower' that you mention, never goes outside. The room itself is simply round, but can be inside the dungeon, interconnected by the rest of the tunnels.

Same goes for Pharos, start in the basement, winding your way up in a spiral pattern to the Lighthouse at the roof.

Now, as for the Turn 6 point, I can't remark on because the only times I've actually done it, I've been with people who had a short cut and have never actually ran the actual first turn from start to boss.