Hey Ryat, I just want to point out an inconsistency in your lore.
"As such I am the most senior TEC officer and as such I am hearby taking command of this fleet until one of the three listed is able to return to duty."
As Carbon has pointed out multiple times now, the UE isn't part of the TEC (aside from the use of it's technology) and doesn't give a damn about it's rankings or structure. Having that sentiment ingrained in their thinking, their ship crews wouldn't give a rat's ass that your character has a higher TEC rank. They may not squabble over who's calling the shots while they're under attack in an effort to maintain a coordinated response, but the reasoning for taking command is weak at best and would likely provoke a less then desired reply.
Well command structures in such a fleet from multiply nationalities usually have an internal command structure already agreed upon by such an event that takes in such issues.
For example, technically Duke Edmenton is a Fleet Admiral and Xenon's rank is lower than that, but the Duke is fourth on the command structure list due to what you just pointed out. So he did have the authority to say what he said, even if his choice of words wasn't as proper.
