Scroll down to "Secondary Spectrum" and look at the graphs of focus shift wrt wavelength for different kinds of lens design. SFX200 is only sensitive to about 750nm, which is only just off the right (red) end of those graphs, which means there is very little difference in focus between the most-extreme part of the spectrum it can see and what you can see. If you use (say) a red-25 on SFX, then about 80% of the exposure is visible light anyway! Even if the IR image was visibly focus-shifted, it's about 2 stops down.

HIE was sensitive past 900nm, which means it could have significant focus shift even on otherwise well-corrected lenses.