How to get a university to make an admission decision more quickly
Universities are aware of this problem. I suggest you either email or call the admissions office at both universities and tell them exactly what you said above, without naming the other university. For the first, ask for an extension for acceptance. For the second, ask whether they can inform you ahead of time about your application. They may or may not be sympathetic to your problem, but at least you'll have tried everything. Do note that if both universities simply say, "sorry to hear that, but we cannot do anything different," you will simply have to make a decision with limited information. Best of luck!