Got it working even if the prop is a bit big 
The fact is that in your fxmanifest, you are loading this as a map but in fact you have to specify your .ytyp file so your fxmanifest will look like this:
fx_version 'cerulean'
games { 'gta5' }
name 'vsFingerprintScannerProp'
author '[VS] Piet'
description ''
version '1.0.0'
data_file "DLC_ITYP_REQUEST" "stream/prop_fingerprintscanner.ytyp"
source: custom prop loading tutorial and example of a custom prop resource