It is possible that the coin has been dipped, but the toning color scheme is pretty common for Dansco toning and it does not scream dipped & retoned IMO.
This seems to be happening lately. I had a submission last year that included a Mercury Dime that was details graded for improper cleaning despite the fact that the coin showed no signs of cleaning. As you can see, my Mercury Dime was also freed from its prison and was sold raw. Additionally, I have encountered several SLQs that have received phantom "improperly cleaned" grades in the last year as well.
It's too bad they don't give a little bit more of an explanation for the cleaning designation...but, I suppose the more time they take with each coin means the fewer coins they grade per hour and less money. Sometimes on these "mystery" coins, it would be nice though.
Looking at the first pic there are some hairlines on the bust... but as they say 'imp. cleaned' it could also be a lack of luster... from my experience they're hard to dipped coins.
Case in point, this coin was from the same album and in the same submission to NGC. I am very happy with this coin.
I agree...this post makes me even more suspicious after the first coin. Sometimes, luster can appear muted in a picture based on the photography technique. Assuming photos of both these coins were taken in the same way...that fact that this coin shows quite a bit more luster makes me think it's not the photography.
I actually had to use axial lighting on the second coin because of the shadows my flash was producing, that gives it a more lustrous look.