Yup, if he grabs you, there's no way of breaking free of his grab.
I'm iffy on the fatty speed change - IIRC, in the previous iteration of the game, I was able to either outrun him or outmaneuver him even on his charge. Now he's considerably faster than me while we're both running, making the first mission's second floor much harder (especially if he instantly aggros before I'm able to move the drawers to block/cheese his pathing). He also is able to follow me much more easily into the back room so that I'm forced to quickly dispatch the zombies there in a crowded space.
It does help that the dodge mechanic is implemented, and I enjoy the challenge at least, even if I'm dying much more frequently now. IMHO, there should be SOME sort of struggle mechanic difficulty. For instance, escaping from regular Z's is TOO easy, while it's impossible to escape the fatty. It'd be great if getting caught multiple times, or being injured/unclothed makes it HARDER to escape, while allowing the MC some sort of ability to escape the fatty.
Also, kudos to the dev for at least fixing the Mission 3 ending bug quickly. I'm still not excited about the lack of anims and new enemies, but I appreciate that they're at least receptive to the community in this regard.