It was definitely speculated this could happen as soon as he launched the coin, not sure if there was any concrete evidence of it like this.

I guess I would hope it takes more then that to rise to the level of obstruction.

Additionally, you have to prove intent, and unless the judge was careless, I doubt they will ever be able to do that. I'd bet the prosecution knows this, I don't think they expect the charges to stick. It seems this arrest was done to send a message.

More evidence of that is that typically in this kind of case they would invite her to show up somewhere to accept process, not be arrested like a common criminal.

There doesn't have to be, it's up to the prosecution to prove the reason was to aid him in avoiding arrest. The judge doesn't have to provide an alternate reason.

How in the world is this an arrestable offense. Escorting someone out of a room?

Another example: https://theintercept.com/2015/11/19/an-fbi-informant-seduced...