Nashers. You are on the right track there.
PIC = Capt.
If the F/O logs hours as PICUS (ie. to reach 250 hours PIC time to unfreeze the ATPL) the capt has to co-sign the PICUS hours in the log. Normally you need company approval for PICUS hours, because it is related to your upgrade. Don't worry, when that time comes they will tell you (and maybe even roster you) for PICUS flights where you make all the decisions under supervision of the capt.