Yes it's written in here :
https://sfzformat.com/opcodes/fil_veltrack

And yes, rgc sfz also have the fil_veltrack range of -9600 to 9600 cents.
But both DropZone and sforzando have the range of -12000 to 12000 (10 octaves).
sfizz currently limited at -/+ 9600 too, so I request for range increase to -/+ 12000

<region>
sample=*noise
amp_veltrack=0
cutoff=19.53125
fil_veltrack=12000