A20.551 If in the same hex as the enemy unit, the prisoners are rearmed no matter who or how the enemy was killed.
A20.551 "One attacking Unarmed friendly unit of equal or smaller size is rearmed immediately for each armed enemy unit it eliminated/captured in CC (or by any other means if no other enemy unit is currently in the same Location)"
If the unarmed unit is in Melee and an enemy unit (possibly its guard) is eliminated not by CC (e.g. by fire on the IFT) but there are other enemy units in the Location, the unarmed unit is not rearmed.
If the unarmed unit is in Melee and an enemy unit (possibly its guard) is eliminated by CC, but the unarmed unit does not participate in the attack (e.g. it is not attempting escape yet, or it did not attack that unit) and there are other enemy units in the Location, the unarmed unit is not rearmed.
The odd case is where an enemy unit is eliminated in CC and there is no other enemy unit, but the unarmed unit did not participate in its elimination. For example a prisoner squad is being guarded by an enemy SMC. There is also an enemy halfsquad in the hex and another friendly non-prisoner unit. The prisoner squad attacks its guard and eliminates it. It does not re-arm because its guard was only a SMC. It is still a prisoner because there is another enemy unit that can take over as guard per A20.5. The halfsquad is now attacked by the other friendly non-prisoner unit. It eliminates the guard halfsquad. The prisoner did not eliminated its new guard. What is not clear whether "by any
other means" should be read as "by a non-CC attack" or as "by a non-CC attack *or* a CC attack which the prisoner did not participate in".
There are two clear cases where an enemy guard unit can be eliminated but the prisoners are not re-armed. I personally think the prisoner should be re-armed in the third case, but the term "other" could be read in a couple ways.
JR