Ruthless Stroke (Prime Dagger weapon skill) has wrong weapon skill modifiers?

Platform: Windows 11
ISP: FUZ
Type of Internet Connection: Fiber
Internet Connection Speed: 600 Mbps
Date & Time: Aug. 22, 2023 20:42 CEST
Frequency: All the time
Character Name: Baniak
Race: TaruTaru
World: Bahamut
Main Job: RDM, Lv.99
Support Job: DNC
Area and Coordinates: Sortie, whole map
Party or Solo: Party with 5 members
NPC Name: None
Monster Name: All
Steps:
I'm using Ruthless Stroke with "stage 3" Prime Dagger Mpu Gandring in Sortie and from my tests Ruthless Stroke has around 25~30% DEX and VIT modifiers. All the other weapon skills exclusives to Prime Weapons seems to have modifiers matching +25~35 Stats visible on the weapon (for example Origin seems to have 60% STR and INT modifiers, while Foenaria (Prime Scythe) has +25~35 STR and INT). Aren't the modifiers for Ruthless Stroke a bug? Shouldn't they match +Stats on Mpu Gandring, so around 25-30% of DEX, AGI and CHR?