Might be onto something lol. I dont think our rear passengers need cold feet anyways 8)Maybe something like this from a different platform could be close enough to work for us?
Under Seat Air Deflector 4Runner 2010-2024 GX460 2010-2026 Ventilated Seats Airflow Redirect - Crossroads 3D
[FITS LEXUS GX460 2010-2026] [FITS 4Runner 2010-2024] Boost your ventilated seat comfort with this custom under-seat air deflector! Designed to redirect hot or cold air from your floor vents directly upward into the seat ventilation fans for faster cooling/heating. • Fits Toyota 4Runner...crossroads3d.com
I should measure something and see if I could 3D print something to fit