I think Oda is building up to Kiku big moment
Kiku ability is about her slashes last a long time, nothing is random with Oda, he made her explain her ability to Kanjuro as build up to this
if the scabbards were gonna lose next chapter Oda would've taken Kiku out, not just take her hand but still in the fight
Scabbards will force Kaido to use Base form, but it won't be easy, which is good for both the scabbards and for him
also its possible that Kaido can't heal from Oden scar due to his mental state, similar to when BM durability wear down she MC photo broke, once he get past his fight against Oden he will be able to heal even from that