This is an interesting angle that I hadn't thought about.
A common take here is that JS was lying about what MS was wearing because she was lying about seeing her getting ready in the morning. I took JS's statements about what MS was wearing to mean that that is what she was told by the last person to have seen MS (SS) and anything more than that. LE was also reporting that that was what MS was last seen wearing, and no one has suggest they were "lying" about it.
But if JS was saying she saw MS get ready in the morning (which based on
the incident report it seems like she did say, but I'm still hedging until her actual words are known), she would know what MS was wearing. If JS participated in MS's murder or the subsequent cover up, she would also probably know what MS was wearing (MOO, but I don't believe if JS is involved that she would be willing to participate without seeing MS's body). So if she was lying about seeing MS in the morning in order to cover up that MS was already (allegedly) dead, why wouldn't she get the clothing right?