They did not go through Kuwait, they were assigned there, doing port and river security work. They were being reassigned to Bahrain, probably to guard that port, or for refurbishment beyond the capabilities in Kuwait, or as preparation for being shipped back to the US. They may or may not have been replaced with another pair of boats in Kuwait. If they were, the new boats likely got to Kuwait before these two left.
I, Travis, and others, don’t think they were in Irainian waters when taken. Likely they were swarmed by a bunch of smaller, but heaviliy armed, boats, while their radios were Jammed, and their GPS either jammed or spoofed.
It’s possible they were in Iranian waters, due to their GPS being spoofed, but it seems unlikely, since they also had radar, and could “paint” the coast to compare to what GPS was telling them, and could compare what GPS said their heading was, with their compass.