using the Linos(Rodenstock) software I gave the link for, here's what you get for 90mm and 210mm lenses.

www.visualperception.co.uk/lfpf

in both cases I have set the aperture to f32 since setting it smaller causes the coc spec of 0.1mm to be broken, i.e. coc becomes larger because of diffraction( although thats probably not the correct terminology)

note also that in both cases the effective f no is f64.

so to answer the original question, your are correct, what you are trying to do is limited by the physics of the lenses and you will get very narrow dof, around 13mm for a coc of 0.1mm.