Worker mode is more important for high poly objects that have animation and/or lighting. For low poly / static, do not use worker mode.
Viewing post in Construct 3 3DObject Plugin comments
https://www.mediafire.com/file/7xw976zjdqha96d/3DLighting.c3p/file
here u go
EDIT: model does not load in worker mode unless you look at the ground.