wallah - yalla

Hi to all.

I would like some assistance to translate these words in my language.

From dictionaries:

Wallah (Arabic)= I swear by God/Allah, but often used as "I promise" or as a filler word/cultural marker.
Is "I promise" a good translation when used in sentences?

Yallah=hurry, but often used as a filler, similar to "okay", "you know" etc, or as a cultural marker.

Examples I've encountered.
1) Two gang members discussing.
A: Do your job or you're dead!
B: Okay, I'll get him today, .

2) Two adults discussing.
C: Man, these kids nowadays, they are so soft, . In their age, I was treated like s**t.
D: , don't mind them.

3) A man plays with his son in the countryside with a ball and speaks:
I throw the ball and whoever gets it first wins. Yalla, yalla, run!

4) That same man sees a dangerous guy approaching, probably an assassin, and calls his son to come back.
Sami, come. Throw the ball and come.

Questions:
1) First example, I believe "wallah" here does mean "I promise". Promise to do the job. Right?
2) "Wallah" is similar to "I'll tell you/Let me tell you" here. Right?
What does "yalla" mean here?
3) Can I drop yalla in "Okay, yalla" ? "Okay" and "Yalla" have the same meaning here, right?
4) Totally confused here.

They both mean a lot of different things. In these examples, more or less:

1) 'I swear'
2) 'I swear'/'honestly'/'I tell you', 'ehh' (this use of yalla has no obvious English equivalent that I can think of)
3) 'Go!'
4) 'Let's go'

Thank you, that's very helpful.