Can someone please baby step me around this TA i really dont understand the last part.

Dual target Range attack I deal 2 to the character using the TA and 2 to the Friendly Adj Figure. The attack KO's them both the TA will not trigger.

The adjacent character might be a part of the attack, like Energy Explosion, Pulse wave, quake, etc. If they die from the same action that killed the Suicide Squad member, they don't get to heal, because they were KOd as well.
Does that answer your question?

Curly, Larry, and Moe all have Suicide Squad TA and are standing in a row. Bill Murray has three lightning bolts, and shoots Larry (who is in the middle) using Energy Explosion. All three stooges are hit by the attack. Larry takes enough damage to KO him. At this point Curly rolls a four for the TA, and Moe rolls a 6. Curly then takes his three splash damage, but doesn't die. Moe takes his three as well, and it is enough to KO him. Bill Murray places an action token on himself, and his attack finishes resolving. Curly then heals two damage due the four he rolled when Larry was KO'd.