You are right, the O line and Cook are elite. But if they didn't have Allen and even with a star DE as a result of the CAP savings, the Bills are a 500 team.
To be fair I think not having Bishop on the field for that drive was the main cause of this. Bishop has improved so much and is playing at such a high level that having him out of the lineup for that one drive was very noticeable.
This is a fair question and points to the defensive game plan preparation. There is no doubt that in most of the Bills games this season - wins or losses - the D plays much better in the 2nd half. They need to fix this or thy will be one and done in the playoffs.
The best form tackle I've seen during the last 10 years was the one where Cooper DeJean did that exact same thing to King Henry. Now that was impressive.