Need help in appending to RDEPEND of another recipe from your recipe

Question

Yocto newbie here and seeking advice as to how to append variables of another recipe from my recipe. To provide more context lets say there is a some recipe file packagegroup-common.bb defined in a package that i cannot modify and i need to run tests of my package.

inherit packagegroup
    
# Only include for debug image
    RDEPENDS:${PN}:append:variant-debug = " \
        framework-ptest \
        inputd-ptest \
        foo-test \
        ... \
        "

is there a way to append to that variable from my recipe bar.bb basically my recipe looks like

    SUMMARY = "Bar"
    DESCRIPTION = "Bar Recipe"
    LICENSE = "CLOSED"
    
    DEPENDS = "bar-interface googletest"
    
    SRC_URI = "git://zzz/Bar;protocol=ssh;branch=mainline; \
               file://run-ptest \
              "
    SRCREV = "zzzzzzzz"
    
    S = "${WORKDIR}/git"
    
    inherit cmake ptest
    
    do_install_ptest() {
        mkdir -p ${D}${PTEST_PATH}/tests
        cp -rf ${B}/src/test/Bar ${D}${PTEST_PATH}/tests
    }
    
# workarounds that i have been trying are

    IMAGE_INSTALL:append = " bar-ptest"
    CORE_IMAGE_EXTRA_INSTALL:append = " bar-ptest"
    
    
    RDEPENDS:packagegroup-common:append:variant-debug = " bar-ptest "
    RDEPENDS:${PN}:append:variant-debug = " \
        bar-ptest \
        "

But nothing is working so far, seems like you have to add bar-ptest in packagegroup-common.bb RDEPENDS to run ptest-runner bar because otherwise i am seeing the error message

bar ptest isn't available.

If i run ptest-runner -l , i am able to see all other ptest specified in RDEPENDS of packagegroup-common.bb. Any advice or insights or workarounds for this issue is greatly appreciated.