HELP! Red Eyed Tree Frog

[Jeppie92]

She just passed away I just got him Sunday. I have no idea what went wrong. Any insight would help right now. Her temp in her tank was perfect her humidity was perfect. Everything was great until about 5 mins ago when she just basically went into cardiac arrest. Before you buy these guys do you look at them? Do you suggest looking at them in detail? I have a ball python but this is my first time buying a frog from someone. Im so... speechless... because I really did everything by the books for this guy... at least I thought. Looking at her though it looks like she had some small red dots under her belly. And I don't think she was missing any toes the one just looked in flamed. I attached more photos of her foot and of her enclosure.

Ps. Heather I wish I got your answer sooner =(