It is not the first time I had a problem with her voice correctly uttering the vowel. I'm not an English native (I am a Romanian native, which is close to Latin) and for me the distinction between e /e/ and i /i/ in Latin is extremely obvious. If we were to draw a mouth diagram with a vowel quadrangle on it, she should definitely migrate the uttering of that particular /e/ from a near-front, close-mid position, to a front, close position. Just like in the English word "tissue".
Yes, she is usually really good about differentiating between the vowels but here (probably the recording) it really sounded like an /I/ (short English i as in the word "if). I also wrote down "studetes." Luckily DL was tolerant of my "typo." =D
The problem is the idea of a "short" vowel in English, which is not "short", but rather has a different pronunciation, closer to a schwa. For some reason, many English speakers are taught to use this as the "short" Latin vowel pronunciation. That's incorrect, as every Italian and Spanish student of Latin knows, but it's quite common, both among Americans and UKers. I believe it's fundamentally because English misuses the idea of a "short" vowel, and that leaks over into Latin. But I would think college-level Latin speakers would know better. I am rather surprised at this pronunciation being so common in this course. Obviously, that's how many English speakers of Latin were taught.
Report it with the report button. It's not very useful to list what is rejected here, because the course is still in beta. (maybe it's a bit useful, to see what is possible through).