First off I just want to say that, guys, it's game. I know this is SL and it's serious business gais, but it's not. Now then, on to why Masane is sealed.
She found it odd that he would try to interlock their fingers. This was completely unnecessary for what she was doing so she did not let it happen. She was sure to keep her her hand were it was. The girl was able to funnel her chakra into him with the contact that they already had. ( c )
(2d4h) <||||> Uchiha 爆弾 Masane Her eyes narrowed and in that moment she realized that this man was indeed an enemy.
That right there is how you have, essentially, sealed your fate. No pun intended. The rest of your post before that is basically you admitting that you would usually not have trusted him, but let it get this far because you wanted your brother's life to be restored. In other words, you're saying in character that you messed up. Now, with that post you're insinuating that you know he's going to attempt to seal you because your chakra's are connected and you can now 'feel' each other. That's all fine and dandy, but therein lies the problem: Yujo never gave off any killing intent or malignance. Due to that, it is, in fact, meta-gaming to now know he's planning something. Add this to the fact that, as Mei has pointed out, you are sleep deprived and, therefore, have slower reactions leads to you not being able to react in time even if you did know he was planning something. Being a ninja/superhuman has nothing to do with it as a lack of sleep is still a lack of sleep to the human body.
All in all, you trusted him fully until you saw his post trying to seal you and then all of a sudden tried to pull something to know what he was doing without it coming off as meta-gaming; however, you've failed at that so it did come off as meta-gaming. So, in other words, you're pretty much done unless Yujo is going to let you repost.
Do note, by the way, that this all my 2 cents on the topic because it's been going back and forth for so long. I'd say it's just my opinion as well, but we all read the same thing and what's there is there, so yeah.