Cut ring anchor to enlarge window

Dear experts,

the triangular window (see photos) is to be replaced by a rectangular one that widens downward. For this, the ring beam below would have to be cut through. The structural engineer said after a brief look that this is not a problem. But now, shortly before the installation of the window (specialist company), I am a bit uncertain. There are static calculations and plans from 1994 when the annex was built. If that helps you with an assessment?!

What do you think?
Many thanks!

Addendum: There are static calculations and plans from 1994 when the extension was built. If that helps you for an assessment?!

The structural engineer said after a quick look that it was no problem.

Then he can also give it to you in writing for a small fee. I also don't expect any problems, but IF it does come to that, you are the one screwed, not the structural engineer you saved yourself.

You are completely right, but upon inquiry I received a message from him yesterday that I should contact someone else, as he stopped his activity on 15.8.… Another contacted structural engineer will only be available in 3-4 months…