That's the good news.
The half-baked part? Look what the corresponding dialog to select by element ID says to use to separate multiple object IDs.
Yes, that's right, this dialog says it wants semi-colons (;) and not the commas (,) given by the Element IDs of Selection dialog.
Happily, there is a solution! Just ignore the lying text and use commas anyway. The dialog honors both semi-colons and commas for multiple IDs. See! I did provide a solution!