create cell vesicle with metaball

I need to indent a plane (cell wall) and split a vesicle of inside the cell. The inside of this vesicle needs to be visible.
I used a set up with metaballs and a boolean to reveal the inside. I gave the cell wall some thickness with a cloth tag. This sort of works but because of the metaball mesh a cloth tag is not an ideal solution. I need high amounts of smoothing to get a acceptable look.
Can you help me with another approach for this.