INCLUDEPICTURE use an alternate jpg if MERGEFIELD "filename".jpg is not valid - mergefield

Question

I keep track of hikes we do in an EXCEL spreadsheet. I use WORD to create journal pages using a lot of MERGEFIELDS. I have clean maps of parks. After we do a hike, I use an editor to draw a route on the clean map of where we hiked producing a route map.
I would like to INCLUDEPICTURE the route map if there is one, otherwise a clean map. For these examples "Death Valley Map.jpg" does exist, "Death Valley Map Route.jpg" does not exist.
I cannot see that "{ IF TRUE ..." ever does anything. Is there some WORD option or switch that needs to be set? My problem is that I cannot get any if test to branch false when the file does not exist.
Test Case
Test Result
{ IF "Death Valley Map.jpg" }
null
{ IF "Death Valley Map Route.jpg" }
null
{ IF "Death Valley Map.jpg" "GoodA" "BadA" }
GoodA
{ IF "Death Valley Map Route.jpg" "GoodB" "BadB" }
GoodB
{ IF TRUE "Death Valley Map.jpg" }
Death Valley Map.jpg
{ IF TRUE "Death Valley Map Route.jpg" }
Death Valley Map Route.jpg
{ IF TRUE "Death Valley Map.jpg" "GoodC" "BadC" }
Death Valley Map.jpg
{ IF TRUE "Death Valley Map Route.jpg" "GoodD" "BadD" }
Death Valley Map Route.jpg
{ IF { IF TRUE "Death Valley Map.jpg" } "GoodE" "BadE" }
GoodE
{ IF { IF TRUE "Death Valley Map Route.jpg" } "GoodF" "BadF" }
GoodF
{ IF { IF TRUE "Death Valley Map.jpg" } <> "" "GoodG" "BadG" }
GoodG
{ IF { IF TRUE "Death Valley Map Route.jpg" } <> "" "GoodH" "BadH" }
GoodH
{ IF { INCLUDEPICTURE "{ IF TRUE "Death Valley Map.jpg" }" \d } "GoodI" "BadI" }
GoodI
{ IF { INCLUDEPICTURE "{ IF TRUE "Death Valley Map Route.jpg" }" \d } "GoodJ" "BadJ" }
GoodJ
{ IF { IF TRUE { INCLUDEPICTURE "{ IF TRUE "Death Valley Map.jpg" }" \d } } "GoodK" "BadK" }
GoodK
{ IF { IF TRUE { INCLUDEPICTURE "{ IF TRUE "Death Valley Map Route.jpg" }" \d } } "GoodL" "BadL" }
GoodL
{ IF { IF TRUE { INCLUDEPICTURE "{ IF TRUE "Death Valley Map.jpg" }" \d } } <> "" "GoodM" "BadM" }
GoodM
{ IF { IF TRUE { INCLUDEPICTURE "{ IF TRUE "Death Valley Map Route.jpg" }" \d } } <> "" "GoodN" "BadN" }
GoodN
Screen shots in case I didn't type exactly:
screen shot of test cases
screen shot of test results