Yes, you will have to re-do those girls in order to get the correct stats and so.
Btw I know that Blackthorn gives a + for that passive for lower hp but, will the other girls (not incluing the two in the update you fixed) give your skills that you already have a level as well? cause when i picked that option for the girl with water powers I thought my ice level would go up a level but it stayed at level 1 so thought i let you know about that in case yes you were meant to gain a level in ice powers but didn't from her if only more stats that's fine. something to check i guess and see if it happens with the other girls as well. Edit: Yeah Rebootlove I just checked it out with Lufilia about 3 to 4 times and didn't get no stat ups or level up to Ice powers from her so that means she's having the same problem that Tamakats and Riamora were having before you ironed out that bug