It might be a shame to make decisions about undergrad based on future grad school costs. It is hard to tell, which is your problem 
As you said, there are many ways to be around animals.
Does she feel pressure to choose a career before applying to schools? Can she just apply to schools undeclared, and try out some courses, explore without making it about a future job? Of, if she really wants engineering, could she apply for that but make sure it is a school she would still want if she changes her mind?
With her stats and ability, she could get into some really really good and interesting schools. I understand the financial challenges with college costs, but maybe some schools will offer aid in various forms that you don’t expect, including merit.