～てどうしようっていうんだ

Hi! I'm Annick and a newbie here, I hope I'm doing things in the right way. I need help with
～てどうしようっていうんだ
Here I have a short, incomplete and out of context sentence (sorry about that):
あいつを抜け出させてどうしようっていうんだ
and two English translations:
"But even if I had helped her get out there? Then what would I had done?"
"I even thought about helping her escape…"
To me both seem right, the person is wondering about his own behavior but is there a better way to say it?
so it's: -te form + doushiyou + to/tte iu ＋no/n da/desu
どうしよう: what should I do
っていう: called/say
んだ: (explanation or emphasis )
I'm not sure I understanding どうしようっていう well, "what am i doing?" "what the meaning of this?" it would be great if someone could help me with this.

Also: In the post here we are saying: "～てどうするの/んだ and ～てどうしようっていうの/んだ are interchangeable". but not completely the same, could someone explain me the nuances please?
Thanks

Annick said:

Hi! I'm Annick and a newbie here, I hope I'm doing things in the right way. I need help with
～てどうしようっていうんだ
Here I have a short, incomplete and out of context sentence (sorry about that):
あいつを抜け出させてどうしようっていうんだ
and two English translations:
"But even if I had helped her get out there? Then what would I had done?"
"I even thought about helping her escape…"
To me both seem right, the person is wondering about his own behavior but is there a better way to say it?

Click to expand...

The former is more accurate or literal. The speaker is wondering what they should do after having her get out/escape, not wondering if they should have her get out. (Of course they are actually wondering if it's meaningful or not to have her get out.)
As in the thread you are referring to, the subject of どうする can be the addressee depending on the context.

Annick said:

I'm not sure I understanding どうしようっていう well, "what am i doing?" "what the meaning of this?"

Click to expand...

It's more likely どうしよう / っていうんだ. っていうんだ is a set, asking intention.

Annick said:

Also: In the post here we are saying: "～てどうするの/んだ and ～てどうしようっていうの/んだ are interchangeable". but not completely the same, could someone explain me the nuances please?

Click to expand...

～てどうする and ～てどうしよう | Japan Forum
～てどうする and ～てどうしよう | Japan Forum

Thank you very much!