Im sorry but a thread dosent work like this, These threads are uses for training for IFATC and are usually supposed to be pattern work and similar things. These are not for normal flights as much as they are for training and challenges. You have to be under active IFATC training to make a thread and when you do you cant choose what comes.
You are not allowed to decline aircraft based on the airline I am pretty sure, the IFC is meant try to be fair and equal, not telling people they can not do things. This is especially the case with ATC just to keep things fair