Something is wrong there Stu and would check it out with Motability.
Like Markw said Motability are on the ball for flagging up a new car, mine appeared within 24 hours.
The dealer could be sitting on the order but its a risky game because the cars could be withdrawn from the scheme and the dealer is able to sit on the order any-ways after sending the order to Motability.
When your sat at the dealers giving all your info to the sales guys they should be filling in an online form on their computer that’s directly linked into the Motability servers, hence, why it should show up in your account very quickly.