When Meg and Alison find Harm's billfold and look at his ID card, that card shows his rank as lieutenant (rather than lieutenant commander), and it shows a social-security number different from the one which he recites to his Chinese captors.
Lishi is not a Chinese surname either in Simplified or Traditional Chinese.
Per this episode, and others, Harm's father was shot down over Vietnam on 24 December 1969 while deployed aboard USS Ticonderoga. USS Ticonderoga (CVA-14) was in the states at that time. She arrived back in the states 18 September 1969 and did not deploy again until 11 March 1971. In episode 5.11, Ghosts of Christmas Past (1999), it is stated that Harm's father was flying in an A-6 Intruder. Tico never had an A-6 squadron.
When Harm says, "I didn't think of using a pillow", his lips say "I didn't think fast enough".