Interesting dawg, this just happened to me also and I spent hours figuring a way around it.
first off, Scotland yard is no longer a national wonder so it is not your problem.
You can check in the BTS directory where the game is installed for a txt file that may clue you into the error. I searched high and low all over the web looking for a solution. I went back to a couple of different saves that were no more than six turns back and they all turned out the same.
Honestly, what I wound up doing was changing virtually every variable I could. The build in every city, the tech I was researching, throw in a civic shift. If a random event pops up, change what you originally did. Then, just keep hitting the green and power through your turns until you hopefully pass the hiccup.
I really wish I would've documented exactly what I did. However, it was 2 am on a saturday night when the problem first cropped up and the game was 1884 and I was less than 5 turns from launching. I went to bed finally a little before 6 am all strung out and tired. If only the game had been 1000 years earlier, I'd have just restarted.
Good luck, I will download your save and check it out.