lol but seriously comparing jabra to kaido is hysterical, no Sanjis flames are not damaging Kaido.
this was all explained in Wano on how to effectively damage Kaido, the only real damage Kaido actually took was from separate Conquerers: Zoro scarring Kaido with Enma/Ashura, Luffy Pre-G5 w/AdvCoC & 3 of his strongest G4 based moves, Yamato in a direct 1on1 conquerors battle. - 2/3 were using AdvCoC, Sanji doesnt even have AdvCoA.... Sanji is still an arc or 2 too early to damage Kaido. Hell he still struggles hurting BM.
Kaido took slight damage from sound based attacks from Killer but didnt do much of anything and neither did Kidds attacks, Scabbards just focused on his prior scar and that was the extent of it & even Laws internal attacks did jack shit to kaido
Sanjis flames are not bypassing anything, Kaido is literally a fucking fire dragon, if at best the sanji can do is superficial "damage", simply sightly burning and shockwave effects which do no significant damage to Kaido, would be less significant than killers
Crux is 135473473647368474% correct in you need internal damaging attacks to bypass Kaidos Haki infused Dragon Scales + Onii Buffs.
in this case: sanji=scabbards in damage output against kaido.
jabra would get absolutely decimated, kaido would laugh at how weak Sanji is compared to Luffy/Zoro and send Jack to deal with him, there is no comparison of kaido and jabra.