I agree generally with Mr. Kirschbaum, although I wouldn't say, strictly speaking, that it's improper for an attorney to attempt to give you odds of prevailing, and in fact, "what are my odds?" is a pretty common question from a client.
The trouble here is that we have far too little information to make anything close to a reasonable estimate of your chances. It's a bit like if you told us you went and bet on a horse, what are the chances it wins the race? We would want to know, what horse? How has it done in the past? What horses is it racing against? And so forth.
By way of example here, you've described how "all of the people in the office loved me," but we don't know whether this is simply your general impression or if there is some (or ideally much) evidence that this is accurate. You've stated that your employer "lied lied lied," but we don't know the specifics, whether they have evidence to support their claims, and so forth. Are they coming in with evidence from "the boss," the "office manager," "another employee," and "another person," and to what extent is the testimony of these individuals impeachable? You mention that you never met the office manager, if you have evidence that your position does not come into contact with the office manager whatsoever, that could be strong evidence to impeach the office manager claims that you "had an attitude" with him or her. We also don't know what the allegations of misconduct are. Having an "attitude" is far too nebulous to win the day, they're going to have to provide specifics, which you haven't provided.
In short, a lawyer who is working close to the case would likely have answers to these kinds of questions and yes, if you can afford to do so, it would make sense for you to seek out the assistance of a qualified attorney. When they've reviewed the matter carefully, they'll be in a position to tell you the odds.
But even then, frankly, those "odds" you hear from an attorney have a very large margin of error and attorneys have incentives to provide odds that are not entirely accurate. For example, before being retained, some attorneys may inflate your chances in the hope it helps get them the job. After being retained, some attorneys may deflate your chances, because they'd rather set low expectations over which they can prevail than high expectations, which may ultimately disappoint.See question