Jap campaign - Guadalcanal SP scenario - bug?

[GottaLove88s]

Guys, I'm playing the Japanese SP campaign, on the Guadalcanal scenario.
For some reason, two of my infantrymen in a 'pocket' in the jungle simply dissolve on turn 5.
They have strength 10 (both) and efficiency 2 and 3 at the end of the turn. They're both in jungle. No enemy units anywhere near them.
I'm bringing paras in to provide a corridor to relieve them.
But they just disappear...

Is this a bug? Or something that randomly happens in the jungle in Guad...?

Mac version of OOB Pacific

[GottaLove88s]

Hey guys, Oops, I think I may have figured this out. I just went back to replay the whole thing from scratch, without moving anything, to see if it happened again, or whether I'd caused it somehow. The two Jap infantrymen disappear when a USMC infantry unit takes the flag for the southwestern 'pocket'. I guess the scenario is primed such that if the flag is taken, any units assigned to guard it, are considered MIA. I was attempting to regroup my units before reinforcing the flag. I get it now. Will stand my ground at all costs... Gentlemen, BANZAI!!!