did you seed the tank with springtails? if so hes probably eating those.
i cant remember how long it took my cobalts to get acclimated to me and the tank. im sure they hid for a couple weeks. now when i open the door they come at me instead of running away
they are about a year old. super bold.
give it some more time. also how old is your baby?
id buy it a tank mate
i suggest placing a slice of banana in the viv for a feeding station. bugs will congregate there and the frog will get used to where they are.
can u post a pic of yr set up? if its very open, like background on 1 side only, i would cover the other 2 sides with dark paper temporarily. so he wont feel exposed if he ventures out. and definitely add leaf litter. 1st time i added leaf litter to my frogs enclosure they acted like it was disney land. now i just put moss on ledges sticks whatever and cover most of the tank floor with leaves.
i get my leaves from the woods, the park, the neighbors yards, :P bake them at 250 for 30 min or so... but theres always a risk of pesticides etc.. so be sure you know where yr leaves are coming from.