Yes, you've marked the diagram correctly. Not sure what the difference is between #4 and #5 in the right diagram, but the hose goes from the nipple under the intake to the white connector that's circled in the engine photo. The #1 in the PCV valve diagram is the same hose (#3) in the diagram on the right.
Without a bigger picture it could be several things
It is possibly the HVAC vacuum supply line
Go easy on yourself and take a few pictures as you disassemble
You should easily see where it goes once you get the upper intake put back on
Do not get ahead of yourself
The VECI is your friend