little confused about pivotal scene (spoiler)

love this movie...just saw it for the 10th time today. there is one part that ive always been confused about and i think i finally got it, but wanted to see if it makes sense. anyone care to help?

its the scene near the end where the colonel meets danny and solomon at digging sites. at first danny tells solomon to tell the colonel where the diamond is...then whispers to solomon "but i promise you he will shoot us both in the head". then danny goes on to scream at solomon to tell where the diamond is. was danny hinting to solomon to keep his mouth shut no matter how much he yells?

but then when solomon seemingly gets the hint and didnt say anything, danny goes back to the colonel and was like "if i get him to talk, we have a deal?" was he using solomon's silence this whole time to negotiate with the colonel? cuz as soon as the colonel agrees with the deal danny betrays solomon and fingers the kid.

did i get this right? was the point of that whisper to make solomon act but then use that act to danny's own advantage of bargaining? if so it was way too subtle i think since it only took me years to finally get it. or im just an idiot.

i hope i made sense....