Retrofit installation of a recessed mirror cabinet

Hello,
I have a partition wall on the side of the washbasin in the bathroom. Here, I have cut a niche for a recessed mirror cabinet. The framework behind it allows for a niche with a width of 121 cm. However, the installation frame of the desired recessed cabinet is 122.2 cm. So, there is about 1 cm missing to install the frame without problems. The wall is tiled halfway up.

Now my question is: Is it possible to somehow saw the framework behind so that the installation frame would fit, or would that jeopardize the stability of the entire wall? Are there other possibilities to get the mirror cabinet into the niche? (Only the cabinet would fit the dimensions) Or am I forced to tear down the upper part of the wall? How should I proceed in any case...

I would really appreciate suggestions or ideas!

A photo would be quite helpful here.

A photo would be quite helpful here.

Photos attached... I wonder if a mirror cabinet can possibly be installed without a built-in frame and if one might be able to make something themselves. Do you perhaps have an idea?

Edit: the lower strip in the frame is not cut properly yet and is therefore sticking out at the top... but that will be straightened.

It's obviously about the profile at the bottom of the picture? I would get a drywall installer. Maybe he can press the profile by one centimeter with gentle force.

To be able to push it down, you would probably have to make cuts at least on the sides. But then you could also completely remove this half. The other half of the profile could remain.

You can still see two other fastenings of rods running to the wall at the bottom. Maybe also downwards?

Depending on how stable the whole thing is built, I would cut out the profile.

Do you have a picture of the unplanked condition?

I just see it’s actually about the width
But the same consideration applies here, simply cutting into the profiles depending on the overall stability.

The other option is simply to omit the expensive installation frame and hang the cabinet on the wall at the back. You should look up which installation variants are basically possible with the mirror cabinet.