Very difficult for me since I do not have your Garmin icon, but I have a theory: some GPS can only display one or two of those Where-To icon. This includes .gpi files made by Garmin or by EPE. I do not know how the GPS decides which one will be displayed: it could be alphabetical, partnumber related or any other priority they set. On some GPS, only one of my 2 .gpi files are shown. No trace whatsoever of the second one. If you imagine that this special Garmin icon (which I had never seen before) obeys a similar rule as Where-To POI, it is possible the GPS will not display it as it can display only one. For fun, try to name your .gpi file as zzz.gpi (using EPE!!!) to see if the Garmin icon will have priority.

For sure, it would help a great deal if I could make it appear on mine. Tell me again which FW and which gps model you have?