Medication for ADHD often shows medium to large improvements in attention and some other symptoms. The medicine likely freed up some brain power that therapy can help her figure out how to use for her benefit. The largest study of ADHD found talk therapy focused on ADHD PLUS medication had the largest improvement in children and teens.
I often say to folks, the medicine lets you access more of your brain power, now we have to figure out what to DO with that extra power and capacity.
Yes, individual therapy with the proper medication and medication compliance will greatly help your daughter.