put dumpdecrypted.dylib in /usr/lib
then
cd /usr/lib
then
execute the command
DYLD_INSERT_LIBRARIES=dumpdecrypted.dylib /var/mobile/Applications/D9DC2DBC-3C80-43E8-AF79-C01480A46271/rcplus.app/rcplus mach-o decryption dumper
you will find the output in /usr/lib
thats it..