I refuse to comment on the embouchure. There is no way that I could offer any advice anyway. Without being next to the player, I see nothing about body use, breathing, tension or anything else. Without that info, no comment is helpful.
Even with a completely messed up face (like after a stroke), consistent attention to the things that do help will help let the embouchure gravitate to its most productive spot. This is the fastest and least frustrating way.
When we change the embouchure by revolution, we can write off range and endurance for quite a while. Well monitored daily routines have many advantages as we do not lose what we have and with small steps our body lets us know what is best. We learn to listen and react. We play with ever decreasing pressure and that alone tightens things up.