A really good/seasoned artist knows how to take it as a compliment when someone thinks they were cheating. They don't get defensive. Just saying.
Also, the FIRST thing I thought when I saw those last images was, 'this dude is tracing high contrast images in photoshop' Especially when compared to your earlier work. The dress on one of the previous characters looks the same. Hey, I might be wrong, and I certainly don't care enough to go find the source images. It ain't that big of a deal.
Just saying, that is how it looks. Maybe you're just 'that good'.