When I took apart an iP4000 I found that the waste pump used TWO tubes to pump ink out of the printhead into the waste pads.
Looking at your last picture it's very likely that both of those tubes you see connecting to the white block (under the yellow wires) will need to be redirected to an external waste tank.
Only way to be sure is to disconnect them and extend them out into a container then try running a cleaning routine. If you get a mess in the container, you were right, if not, you were wrong...