Character mesh rotation not applying outside of editor

I am having a vexing problem that has plagued me for quite some time, and I’m not really sure how to solve it.

For a bit of background, I have a blueprint hierarchy set up like this:
Root_Playable is a parent blueprint in the game I’m creating that handles a whole lot of stuff related to a character’s movement and interaction with the game itself.
Playable_Entity_Acrocanthosaurus inherits from Root_Playable, as do several other blueprints for various playable characters.

The viewport on my acrocanthosaurus has a capsule component, a mesh, a camera and springarm, and several collision spheres necessary for different aspects of gameplay. In order to get my acrocanthosaurus set up correctly such that it faced the proper direction in-game, I needed to set its Z-axis rotation to -90 degrees. This can be seen here in this screenshot:

Just in case, I also posted Root_Playable’s viewport below as well, though it’s for the most part empty. I set its mesh rotation to -90 degrees as well, since all my Playable_Entity_XXX blueprints that inherit from Root_Playable all required a -90 degree Z rotation.

The issue I’m having is that whenever I play outside the editor, this -90 degree rotation on the character’s mesh is not showing up. This is not only the case for the acrocanthosaurus, but for our parasaurolophus and utahraptor as well. Here’s a comparison:

In the editor:

External to the editor (both cooked builds, and uncooked builds launched external to UE4’s editor)

I also have another character blueprint, Playable_Entity_Velociraptor, that works correctly, yet I’ve scoured its viewport settings and they seem to be identical to the three dinosaurs that do not rotate properly external to the editor.

I was able to force-fix this by using Event BeginPlay to apply a -90 degree Z rotation to any character that spawned into the game world, but now that we’ve been moving into multiplayer gameplay, that’s no longer working properly and we really want to solve this bug.

Has anyone encountered this issue before and/or have any ideas on how to fix it? I can provide more screenshots or explanation if need be.