I don't know what your background is but part of the unwillingness of some to accept your veiwpoint is you're saying that you know more than the people who designed the axles. That they basically know less about designing axles and lubrication systems than you do.
I think people may have a problem when it comes down to saying whether you're right, or the people who designed, engineered, and built the axles are right. Maybe they're just hesitant to accept your word over Dexter's. I dunno.
I worked in a manufacturing facility for 40 years and maintained equipment as my job. When we greased a bearing that already had grease in it, we added very little grease, even to 12 and 18 inch roller bearings. Generally speaking we added about 1 shot of grease every couple weeks. Not very darn much, but these were not dry bearings. So maybe the small amount of grease you showed is all that is needed periodically added to an already greased bearing. I dunno.