I often find dark beads along the core of clementines grown overseas. On the odd occassion, one of the beads is clear and transparent. I've attached a photo below. The beads are not fluid; they are hard.
It could be pectin, which is present in the peel and pulp of citrus fruits. Sometimes it can appear in gooey blobs (technical term) inside the fruit but not inside the segments; these blobs may dry down when the tree experiences very dry conditions.
From what I understand you are worried about the beads of juice on the orange slices? Those beads are just juice of the orange, a prick could've caused this or just the temperature change from a refrigerator to the warmth of the kitchen. Nothing at all to worry about.
Water, juices will try to escape their turgidity of the cells surrounding the seeds of the orange. I would pop them in my mouth and savor!
No problem that I am able to see or have even heard musings of a problem. Enjoy that orange. My hubby uses knives to peel an orange...I use my fingernails. I eat with random abandon. The fruit inside that peel is probably safer than the water you drink from your tap in the kitchen sink.