As long as the altitude won’t be an issue, she / you should definitely do the Haleakala sunrise. Book your passes now! They go quickly. Summit is +/- 10,000’ so not a whole lot different than typical passenger jet cabin pressure altitude (usually 8,000’) so I’d bring the O2 machine and confirm with the docs first.
Other things I’d recommend are Lahaina (fun town with lots to do / see), head up to Honolua Bay (there’s a great lookout over it that’s absolutely beautiful), a sunset or two from Launiopoko Beach and a jaunt across the north side to Kahului / Paia on Honopiilani Highway (route 30), unless it’s blocked still. There might still be some amazing swell coming in near Peahi / Jaws so you can go watch the truly crazy (and skilled!) surfers hitting that too! Flatbread Pizza in Paia is great for dinner.
I love Maui - hope to get over there again in a few weeks! Enjoy and feel free to send a PM if you want some other info. / suggestions. I hope you all have a truly wonderful experience! Life is meant to be LIVED and she will feel so utterly alive there! Best to you all! So glad to hear she’s getting to do this!
Some pics for inspiration from when I took a few days and went over there myself a few weeks ago - I’d love to end up there at some point perhaps!:
(Haleakala - you can easily see Mauna Kea and Mauna Loa on the big island if it’s clear)
(Elevation could be an issue for her so please check! Also it gets STOOPID cold up there so dress warmly!)
(Some ok swell near Hookipa Park east of Paia - a fun place to chill out and relax)
(Honolua Bay overlook, the bay itself is great for snorkeling and diving if that’s a possibility. Even if not it’s a beautiful place!)
(Downtown Lahaina - fun place to just walk around, shop, whatever... there are some interesting historical sites to check out as well...)
(A “typical” morning looking west towards Molokai - in background - and Lanai. On a clear day you can see all the way back to Oahu!)
Please let us all know how the trip goes. I hope she absolutely loves it and I’m so glad to hear she’s doing better! Best aloha and vibes sent your way! E Komo Mai!