You can't, by definition, hear ultrasound
It was your math that said 10 GHz gives 140 nm resolution in tissue, which means that you do not have 1 nm resolution. This is science, not magic. You can't just conjure up an answer out of thin air.
The wavelength you can get depends on the speed of sound in the medium, so any calculation for one medium will not work for another medium in which the speed is different. IOW, THz might work in what the article says is the application, e.g. in silicon or other semiconductors (checking for defects in circuits), while not working in e.g. water or air. You have to show it, i.e. do some science.