Question about MVR

I was arrested for DUI in Jan of '07, however it was dismissed and as part of the deal with the prosecution it was not included in my record (I pulled a copy of my MVR and it's not there). My license was never suspended and it was a one time offense. My MVR shows two things on it since 1999:

1. A ticket for doing 15-25 over limit in November of 2010

2. An accident, my fault, all damage to my car in April 2012

Should I disclose the DUI arrest (no conviction).

 

Here's whats going through my head:

1. IL drops entries from the traffic court records every 7 years, the DUI arrest was 02/09/07, after 7 years the only way to see a record is to go to Springfield and look for it!!!

2. Even though it's not gonna show in the MVR, it will show up in a court case check at the clerks office, though the odds of them physically sending someone to check are low (I asked and they only have electronic records back to 2010, thank God for goverment inneficiency!!)

3. I have a job (non CDL), so I technically could wait untill Feb 14 to apply, however, would they hold a DUI arrest without a conviction against me??? If not, and they found out, would they not then hold the omission against me????

4. TMC's application asks about DUI's going back 10 years, even though they state you can have none within the last 5, so does this mean it's not an automatic denial???

I know I'm asking a lot, but I just don't want my nightmare scenario to unfold (get an offer, go to orientation and get sent back from it, without a job!).