Just got the good news that CO agreed to offer a FRA-IAH option. It was requested along with the OS group booking so as things stand right now, if you are taking the OS JFK-VIE-FRA outbound, you can come back on CO FRA-IAH on CO 47. We are holding 15 business seats on the OS and CO flights!^
Amended the post on top of the thread accordingly:
CO: FRA-IAH: 1346$++ in Business (Z) (this request was placed in conjunction with the OS fare, so you may have to take OS J out, CO Z inbound)