So the good news is there's a really simple answer here. The bad news is it doesn't really entertain your last statement. At all. You can't leave information like that out. Especially if you had a variety of these jobs. If you do, you'll have employment gaps all over the place. And then what would your explanation be? I wasn't working? Working hourly or at an unpaid internship is far better than that.
As to your overarching question about which they look at - the answer is both. They give the adcom different pieces of the puzzle. The employment history is an online documentation of your resume as well as the timeline of your post-graduation career. The resume is more for impact, responsibilities, scope, AND story. So it could make sense for some things to not show up on your resume (POTENTIALLY - take that one with a note of caution - there aren't many cases to justify this at your stage in life) but definitely not in your employment report. You have to enter everything. You might not love some of the jobs you've held in the past, but they're better than no job at all!
As for killing your chances - no, it won't kill your chances at the top 15. There are ways to craft a story around it that would make sense. If you don't remember salary information, you can definitely leave that blank and explain it. However, I don't see why you couldn't find that information out. Do a little digging. Worst case, take an educated guess and then explain it. One thing to note is that some applications don't have options for "type of salary" (e.g. hourly, annual, etc.) so in that case you'll have to annualize and then explain that too.
I hope that helps! You're making a mountain of a molehill - some things in life are done. You can't change that. The question is how do you make the most of your experiences going forward. Now it comes down to presentation and story!
Managing Partner, Founder
Critical Square | MBA Admissions Services
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