Rename locators in Maya to null_shape01 & so on & so fourth.
Bake all frames required of camera as well as locators. It will shift the keyed range to start from frame0 in After Effects.
Use this mel script found on Maya Station to clear all junk in file if you have issues saving out as .ma from .mb
There are 3 different types of unknown nodes that can prevent re-saving as a different format.
Unknown nodes, unknown transforms and unknown dag nodes.
The other two are uncommon. But it’s worth mentioning .to delete all three types:
delete `ls -type unknown -type unknownDag -type unknownTransform`
Also, if there are still issues, it could do with left over referencing junk. Turn off Display on DAG objects in outliner and delete everything else but be-careful not to delete the animation nodes.
Last thing is the scaling issue which I will re-write here after discussions.
Scale issues with locators.
Alt Click on the position button of the null and then under expression type - transform.position*100 on all nulls.