It has in the past for me
@SYD but I didn't get the credit. Once with a hertz rental, the pre-auth was just over the spend threshold and I received the Amex email, but when they finalised the rental, the price ended up being just below the threshold for some reason and I missed out on the credit. I now check the final price when dropping off the car and recently, to prevent history repeating, I had to get them to add $2 or so to the amount to hit the threshold.
But in your case, I'd check to see if they have a prepay option because if the settlement date on your statement is outside the promo dates you may not get the credit. I used the 'pay now' option with Hertz and the amount was charged to my card and email received immediately. A new payment or settlement was not created when I returned the car.
The spend thresholds for hire car deals have increased from around $150 a few years ago to $250 - $270 now. This a bit annoying for me as I usually hire for two days and the cost tends to be less than $230 (thankfully, prices are almost back to "normal"). I need to be a little creative to get over the threshold.