We were playing the first core scenario today and a Star Spawn effect instructed us to use a Mesmerized condition, even though I didn't have BTT in my collection. So we can conclude that some BTT stuff has a chance to be included in other scenarios, but also that the collections are a little buggy!
Hah! We had that happen as well! The DLC map I got played a little buggily. It told me to take Mesmerized (we just did Dazed instead), had a little bug where an explore token wouldn't go away (we revealed the next tile, it just didn't go even when we clicked on it and said to explore), and at one point instead of the usual preform ritual text box popping up we got some text along the lines of "INPUT_ERROR_SOMETHING" (it still let us preform the ritual luckily)