Dryer Vent Hose, 6" Insulated Flexible Duct 8FT with 2 Duct Clamps, Heavy-Duty Three Layer Protection for HVAC Ventilation, Duct Fan Systems

I spray between 15-20 PSI for almost everything. The back spray is coming from the inside. I have a dryer vent hose attached and secured with a clamp to vent outside. The fan is mounted directly in the center. The hole on the back is a little bigger than the fan body's six inches, but fully covered by the square portion. Does it need to be airtight? Dryer Vent Hose, 6" Insulated... https://www.amazon.com/dp/B09ZPH5R2L?ref=ppx_pop_mob_ap_share