Request for Help Re: BART

At around 6:30 p.m. on January 31, I parked in the Lake Merritt BART parking lot and then walked across the street to Laney College. When I got back, I found that I had been ticketed. Apparently, the lot is Patron Parking Only. The thing is, there were no signs around indicating that the lot was only for patrons. The only signs I saw were this one and this one. These seem to indicate to me, a reasonable human being, that while there are restrictions on parking between 4 a.m. and 3 p.m. there are no further restrictions after the times posted. Also, I was parking after 6 p.m., so the meters on the street were not in effect, and I could have parked for free on the street.

So I took the pictures above, printed up a letter, and mailed in my plea. It was denied. The letter said that what I'd done was ticketable and that I hadn't shown that I hadn't done it, so there we were. On pretty much the same day, I noticed that numerous copies of this sign had been posted around the lot. I took pictures and mailed in my request for a hearing (and my check for $25, since that was the amount due), and I waited. They granted me my hearing, and when I showed up for said hearing, the appointed Hearing Examiner (not a BART employee) listened to what I had to say, reviewed the pictures that I had taken and told me that he would look for a work order for the posting of the sign; if he found that the signs had been erected after the date of my citation, he said he would dismiss the citation.

Ten days later, I received his results: Not Dismissed:

"Your argument was that there were no signs at that time indicating that the parking lot was to be used by BART patrons only. At some later date you noticed the signs and believe that they were installed after the citation was issued. You did not provide any documentation that would show when they were installed and I was unable to determine the date on installation. Without further evidence to support your argument I cannot dismiss the citation."

So the issue has become this: how do I get a copy of a work order or discover which BART employees installed these signs so that I can demonstrate, concretely, when they were installed? If I could find some proof, I would be happy to pay, up front, the additional $25 it would take to go to the next level with this, but without said proof, there's really no point. In addition, since a further review would be "conducted in accordance with California Vehicle Code section 40230," and said section includes this subsection:

"(c) The conduct of the appeal under this section is a subordinate
judicial duty that may be performed by traffic trial commissioners
and other subordinate judicial officials at the direction of the
presiding judge of the court."

it becomes even more likely that my case would simply be reviewed by some BART clerk of some sort, so my chances of getting a sympathetic ruling are pretty much null and void.

Request: if you know someone who works for BART or who has worked, litigiously, against BART, would you be so kind as to ask how an ordinary citizen would go about getting a copy of a work order? If I can't produce this by June 26, I'll simply let this go; there's really point in dragging it out over $25 already paid.

Many thanks in advance.