3.5yr old having a hard time potty training

My daughter is 3.5yr old and has a speech delay but is able to understand and communicate a few words. She can say poop and pee and understands the concept of going on the toilet. She just does not appear to care one bit about it. She has successfully gone on the potty many times, with great fanfare from me, but just doesn't care to make it a habit.I did naked time for 4 days, bought a carpet cleaner. I did the 3 day potty training book. I bribed her with a doll she wanted I bribed her with a kindle I gave her gummies, marshmallows, m&ms, chocolate chips etc. Every time she went I took away diapers completely and I now have to wash a load of underwear daily and have to keep her away from plush surfaces. I got her potty time dolls, we "potty train" the dolls I got her potty books we read I got her a potty time watch that goes off every 30 minutes reminding us to go to the potty. This was the most successful for about a day.I have 4 kids in all, a 6.5yr old boy and my girls are 5.5yr, 3.5yr and 18m old. The first two were tough but it seemed to "click" for them after a few successes. This kid just has zero care. She will poop or pee in her undies and just walk around like that and refuse to say anything about it.Help! via /r/Parenting http://bit.ly/2RqR4qi