Yep, I know that Viconia sent her to search for the artefact. There were different groups sent out, that's clearly explained in the House of G. quest.
So here, SH could also explain where it was, how she found it and how she managed to get it in her possession. I guess most players will choose to add SH in their party for this quest.
That the Githyanki dragons followed the Nautiloid because they knew the artefact was in it seems logical.
But that the absolutists also knew it would need some explanation. The illithid that were on the nautiloid didn't know it. Else they woudl have taken it from SH.
