Can you do it legally without the exit of 15B facing a wall?

mi-go hunter said:

Don't see any trouble. Just connect 15B's exit to the lower-right quadrant of 17B (in effect, treat 17B as four small tiles). If you connect the full width of 17B with 15B, then yes, you would exit into a wall.

There is a rule for placing tiles that is only in the example for placing tiles (there are many rules hidden in the rules book unfortunately). It states that the tile borders shall be aligned after placing.

Yes, I saw that but I think it's more important to line up the black walls + exit entrance correcly. Then again, is there a scenario that uses 15B and 17B?

Dam said:

The reason this question came up was because this same situation happened in Hive, the 6th mission/scenario. Tile 17B was supposed to be added at the end of level 3, and the last tile on that level was 15B. So that's where the problem came up. I lined up the exit of 15B and the entrance of 17B anyway, but I thought it strange that a problem like that would come up in this game.