C++ Walk trough summon - C++

[Kahras]

Hello, I have a problem!
I changed it in tile.cpp:

if (const Monster* monster = creature->getMonster()) {
            if (hasFlag(TILESTATE_PROTECTIONZONE | TILESTATE_FLOORCHANGE | TILESTATE_TELEPORT)) {
                return RETURNVALUE_NOTPOSSIBLE;
            }

for this:

if (const Monster* monster = creature->getMonster()) {
            if (hasFlag(TILESTATE_PROTECTIONZONE | TILESTATE_FLOORCHANGE | TILESTATE_TELEPORT) && (!monster->isSummon() && monster->getSkull() != SKULL_YELLOW)) {
                return RETURNVALUE_NOTPOSSIBLE;
            }

The script was supposed to work in such a way that summons that have a yellow skull can enter the protection zone.
The problem is that it does not check whether monsters have yellow skulls.
Would anyone help?