I just figured out how to do this (accidentally), and hoped it might be helpful to you or anyone else who wants to do this.
There are two steps - first creating what I will call a “stealth citation” and second manually inserting the text you want in the visible citation.
A “stealth citation” inserts the reference into your references/bibliography without any trace of it in the text. This could be dangerous if not used carefully! By removing both the author name and the year from the temporary citation, it will show up in your references even though you won’t see anything in the text. For instance, instead of putting {Garner, 1974 #1189}, you can instead put {,#1189}. When this is formatted, there will be nothing indicating an in-text citation but it will be in your references. So double-check your references to make sure no extra stealths have appeared.
Then you put the text you want in with the visible citation. This requires the use a character called the “acute accent” and looks like this “`” thing (remove quotation marks). It’s the same key as the tilde key (~) except you don’t press shift; it’s normally the key to the left of the 1 key. It must be placed before the final semicolon. Let’s say you want to see (Felfoldy & Garner, 1971; Handel & Imai, 1972; for a comprehensive review see Garner, 1974) as the final product. If done the normal way:
{Felfoldy, 1971 #170; Handel, 1972 #659; for a comprehensive review see \Garner, 1974 #1147}
Endnote would give you:
(Felfoldy & Garner, 1971; for a comprehensive review see Garner, 1974; Handel & Imai, 1972)
No good. So instead you do (note the use and placement of the acute accent):
{Felfoldy, 1971 #170; Handel, 1972 #659`; for a comprehensive review see Garner, 1974} {,#1147}
Now when you format you get:
(Felfoldy & Garner, 1971; Handel & Imai, 1972; for a comprehensive review see Garner, 1974)
And Garner (1974) will show up in your references! Tada! Sorry for the long and complicated explanation, but hopefully it helps…