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the OP doesn’t seem to have “unsubstantiated evidence.” his/her evidence seems very valid and thorough.</p>
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do the OP’s intentions matter here? the fact is the it is highly probable that the “friend” has plagiarized artwork and might still be doing so.</p>
<p>the first thing the OP needs to do is confront this “friend” and ask what’s going on to see if there’s an explanation. if there isn’t, then the “friend” needs to be exposed, not so much for what happened 3 years ago, but because the “friend” may still be plagiarizing (probably not all her work, but she may be taking credit from time to time and that needs to stop).</p>