What I see in your link, is a topic where the dust boot around the piston looks either swollen or just misplaced due to a caliper piston leak.
1) That is not conclusive evidence of grease damage.
2) Why would they have greased the piston dust boot that much (if any) in the first place?
3) Where was it stated in your above, linked reddit topic, that the piston dust boot pictured, swelled up due to grease? I see no mention of that happening so I've no idea where your post is coming from?
4) Did you use that Permatex on the junction between the boot and the piston or lather it all over the boot? No grease should be lathered all over, and anything between the piston and boot should not have solid ceramic particles in it, but even so, a tiny bit between the piston and boot would not swell the whole boot. I suspect you just had a piston leak.
