Definitely looking a lot better, but I would watch the muscles on the side of the neck - they are looking too pronounced - usually those muscles go towards the back - they would only really show when the lower mouth was stretched - say if he was angry - and even then they wouldn't be that obvious.

Here's a good link that might help and show where everything connects up.

https://www.gwc.maricopa.edu/class/bio201/head/head1.htm