Traditionally Maya has had annoying issues with object starting with digits or ending with digits (or was it just the start?). Anyway, I suspect it must have been related to that.
Here: ayon+settings://maya/load/reference_loader
The you can e.g. also get rid of the trailing slash.
Again, why it’s there? Not entirely sure.
That’s the Reference Node (RN). That’s actually default maya behavior - however, by default reference nodes are hidden in the outliner (Show Reference Nodes) in the outliner menu - it seems you have that enabled.
The name for that reference node I’ve never seen being important for anyone so I don’t think we do much with that ourself. I believe it defaults to the namespace and adds RN by default.