Masters should also come with Spinfits according to the website, so looks like they were missed too. Knowing first hand how amazing Jake and the team are I am sure if you email him they will get it sorted very quickly.
I really want to know the situation with the 2.5mm TRRS cable! It was a big selling point for me.
They are oxygen free copper and balanced until the y-split. If I remember right it was due to the fact that everyone wanted removable cables just in case they wanted to go balanced in the future, so Trinity accommodated everyone by making them balanced until the Y-split.
Now everyone that wants a balanced cable made can just purchase or make themselves a male-to-female balanced cable that will connect the Y-split to your DAC/AMP. I don't remember seeing that they would come with a balanced cable that connects the DAC and your Y-split but I also don't have the greatest memory, this is just some background info so you may still want to wait for a Trinity response to your question.
What kind of source are you using for the balanced connection? I've been wandering if I want to invest some money to hear what a truly balanced connection really sounds like and if it's worth it