It's not like they didn't know that the tress were there from the very beginning or maybe not. It would not require a redesign to save them now if they would have designed around them in the first place. It appears that the new dorms and the parking garage are a canned design (by a development company) and to do a redesign of a canned design would take time and money which they didn't want to spend.
I'm thinking this is the case because they are just now doing the topographic survey, which is AFTER, the design is completed. Typically the survey is the first thing to be done after a site is selected, then site planning follows. At least that's the way I've always done it for the past 30 years. I also suspect that the guys doing the actual day to day grunt work designing haven't set foot on campus. The principal of the firm visited but he's probably a bean counter and hasn't designed anything in years. I deal with out of town people like this all the time.