HVAC / Plumbing Question Range Hood Duct

[Faaz Hafid]

Guys,

Any GC/Plumber/HVAC person comment on this.

doing an installation for a range hood where previously there is no duct going outside but there is a duct going straight outside from one of the gas fireplace (no chimney involved straight horizontal duct outside).

The homeowner didn't want to install a duct (which is an easy option) as the hood wall is facing outside.

The homeowner got someone to install a "Blue PVC Lay-Flat Discharge Hose" approx 1.5" diameter that connects to the fireplace duct (seems like proper sealing), but I have never seen this before, is this going to work if I installed the range hood that has 600-700CFM, wondering if anyone has seen this or have comments about it?