cmake rpath not loading all libraries - cmake

Question

I am writing a program where the build is done using cmake. In the cmake file I setup the rpath to point to the directories of the shared libraries I use. I also have some other libraries such as vtk installed in $HOME/.local/vtk-v8.2.0/lib
if( ${APPLE} )
set(CMAKE_MACOSX_RPATH ON)
endif()
SET(CMAKE_SKIP_BUILD_RPATH FALSE)
SET(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE)
SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
SET(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
LIST(FIND CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES "${CMAKE_INSTALL_PREFIX}/lib" isSystemDir)
IF("${isSystemDir}" STREQUAL "-1")
SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/${libDir}")
ENDIF("${isSystemDir}" STREQUAL "-1")
The rpath is correctly set
$ readelf -d ./myExec.so | rg RUNPATH
$ 0x000000000000001d (RUNPATH) Library runpath: [/home/ashkan/myExec/install/lib:/home/ashkan/.local/vtk-v8.2.0/lib]
but when I check my executable it does not find all the shared libraries.
$ ldd ./myExec | egrep 'vtk'
$ libvtkCommonMath-8.2.so.1 => /home/ashkan/.local/vtk-v8.2.0/lib/libvtkCommonMath-8.2.so.1 (0x00007f2bcf28d000)
libvtkCommonCore-8.2.so.1 => /home/ashkan/.local/vtk-v8.2.0/lib/libvtkCommonCore-8.2.so.1 (0x00007f2bcee4c000)
libvtksys-8.2.so.1 => not found
Also I have checked and the shared library that says "not found" is actually in the same directory as the others.
Any ideas why this would be the case?