Weekend in Paris?
If your schedule can handle it, why not spend the weekend in Paris and take a sub-24-hour MSP connection on the return:
2/25: IAH-MSP-DTW-CDG
2/27: CDG-DTW-MSP
2/28: MSP-IAH
$413 all in at nwa.com
Many employers will go for it if you can demonstrate the savings, such as in this case.
LGW or AMS will be about $443 all in.