Magnus is right. The problem is that if this JUST happened, why would the US give you access after JUST banning you? Makes no logical sense.
Why would a lawyer tell you 3 months? Because they told you something to give you hope...so you would try. Otherwise, no money. I hate to say this, but most lawyers really feel like you are paying them to TRY, not be successful. This lawyer either really doesn't know, so therefore should not be doing waivers, or really doesn't care, which is worse.
I would have told you to wait. I very much doubt you will get approved. When you get your response, if it is a no, they will critique all aspects of the application, but the real reason will be "not enough time has elapsed". Make sure you ask the lawyer at that point....if your are taking money for this service...should you not KNOW I would be rejected?