Sinister means to use subterfuge to deceive or to do something malicious.
Obviously whatever it is it isn't criminal or it would be public record....and I don't think anyone ever hinted at or thought criminality was at issue.
So, I think Jourdan did nothing but further muddy the water on that count.
No matter, clearly whatever it is is serious enough to interrupt a possible NFL career. And, considering what we know of his college past, it would be surprising if it didn't have to do with alcohol/mental health.