This is what your model looks like when I manage to open in fully, Zoom extents, and hide the larger face behind the flowers.
And zoomed in close…
I find it hard to imagine how you will use this model, but it’s what you have.
As an example, I did a screen grab to make one sunflower into a .png image with transparent background round the flower, and applied it to a rectangle with hidden edges, and made it into a FaceMe component.
If you do this for a sample of your modelled flowers, viewed from slightly different angles, and make a screen grab of each view, then save it as an image and apply to a face, you will DRASTICALLY reduce the edge count, to the point where your model should become manageable.
Sunflower - face me.skp
And you could make the image much smaller - maybe a quarter of the size - if you never want a close up.