Leafcutter Bee Nest

I was pruning a Sodom Apple tree (Calotropis procera) in my garden, when I noticed bougainvillea bracts tucked inside the end of one of the dead branches (Pic #3). My husband then noticed the same thing on two other branches still on the tree. Curious, I broke the branch and was surprised to find these pretty pink packages lined up inside the hollow for about 10 cm. Pic #4 shows the obviously cutout bracts that were sealing the opening. We placed the little package back inside the branch, placed it on the ground under the tree, and left the other two dead branches on the tree. Feeling bad about the disturbance I caused, but we'd never seen anything like that before. After some research, we are guessing they are the cells of leafcutter bee nest. The wiki has this to say: "Nests are typically divided into cells, each cell receives a supply of food (pollen or a pollen/nectar mix) and an egg; after finding a suitable spot (often near where she emerged), a female starts building a first cell, stocks it, and oviposits. Then she builds a wall that separates the completed cell from the next one. Nests are often (but not always) built in natural or artificial cavities. Nest cavities are often linear, for example in hollow plant stems, but not always."