How to access needs.job-id.outputs in the container image credentials fields?

Question

I have this workflow

name: my-workflow

on:
  push:
  pull_request:
    branches: ["_.//"]
  workflow_dispatch:

jobs:  
  set-var:
    runs-on: [ self-hosted, linux, enterprise ]
    name: set-var
    steps:
      - name: Import Secrets
        id: import-secrets
        uses: hashicorp/[email protected]
        with:
          url: https://vault-enterprise.my-company.com
          method: approle
          path: approle-busapp
          roleId: ${{ vars.VAULT_ROLEID }}
          secretID: ${{ secrets.VAULT_SECRET_ID }}
          namespace: abc/efg
          secrets: |
            DEV/data/SECRETS a | A ;
            DEV/data/SECRETS b | B ;
            DEV/data/SECRETS c | C ;

      - id: set-var
        run: |
          A="${{ env.A }}"
          B="${{ env.B }}"
          C="${{ env.C }}"

          echo "A=$A" >> $GITHUB_OUTPUT
          echo "B=$B" >> $GITHUB_OUTPUT
          echo "C=$C" >> $GITHUB_OUTPUT

    outputs:
      A: ${{ steps.set-var.outputs.A }}
      B: ${{ steps.set-var.outputs.B }}
      C: ${{ steps.set-var.outputs.C }}

  job-1:
    needs: [set-var]
    name: job-1
    runs-on: [ self-hosted, linux, enterprise ]
    container:
      image: company-artifactory/my-actions-runner-image:latest
      credentials:
        username: ${{ needs.set-var.outputs.A }}
        password: ${{ needs.set-var.outputs.B }}
    env:
      C: ${{ needs.set-var.outputs.C }}
    steps:
      - name: echo
        run: |
          echo $C
  job-2:
    needs: [set-var]
    name: job-2
    runs-on: [ self-hosted, linux, enterprise ]
    container:
      image: company-artifactory/my-actions-runner-image:latest
      credentials:
        username: ${{ needs.set-var.outputs.A }}
        password: ${{ needs.set-var.outputs.B }}
    env:
      C: ${{ needs.set-var.outputs.C }}
    steps:
      - name: echo
        run: |
          echo $C

As you see I am using a custom image name company-artifactory/my-actions-runner-image:latest as the runner image to run job-1 and job-2 in a container and it needs credentials to pull the image.

I am trying to us needs.set-var.outputs.A and needs.set-var.outputs.B to pull the secret form vault but it seems like GitHub Actions do not support this. I don't have access to needs.outputs in the container.credentials.

How can I make it work?

Another concern that I have is sharing secrets between jobs. How do I do this securely? Because right now I am seeing a warning that the secret shared as output is not secure.

UPDATE

I am adding a new version of the question here to clarify one part of the question.

name: my-workflow

on:
  push:
  pull_request:
    branches: ["_.//"]
  workflow_dispatch:

jobs:  
  job-0:
    runs-on: [ self-hosted, linux, enterprise ]
    name: job-0
    steps:
      - name: Import Secrets
        id: import-secrets
        uses: hashicorp/[email protected]
        with:
          url: https://vault-enterprise.my-company.com
          method: approle
          path: approle-busapp
          roleId: ${{ vars.VAULT_ROLEID }}
          secretID: ${{ secrets.VAULT_SECRET_ID }}
          namespace: abc/efg
          secrets: |
            DEV/data/SECRETS a | A ;
      - id: print-secret
        run: |
          echo $A
          echo "${{ env.A }}"
      - id: set-env
        run: |
          AAA="${{ env.A }}"
          echo "AAA=$AAA" >> $GITHUB_OUTPUT
      - id: test-set-env-step
        run: |
          echo "this is a test"
          echo ${{ steps.set-env.outputs.AAA }}
    outputs:
      AAA: ${{ steps.set-env.outputs.AAA }}

  job-1:
    needs: [job-0]
    name: job-1
    runs-on: [ self-hosted, linux, enterprise ]
    container:
      image: company-artifactory/my-actions-runner-image:latest
      credentials:
        username: ${{ needs.set-var.outputs.A }}
        password: ${{ needs.set-var.outputs.B }}
    env:
      B: ${{ needs.job-0.outputs.AAA }}
    steps:
      - name: echo
        run: |
          echo $A
          echo $AA
          echo $AAA
          echo $B
          echo ${{env.B}}
          echo ${{env.A}}
          echo ${{env.AA}}
          echo ${{env.AAA}}

• in job-0 in the step "print-secret" the value of "a" from Vault is successfully printed twice.
• in job-0 the "test-set-env-step" is not printing the value of a.
• in job-1 the value of "a" from Vault is not printed at all.

and based on this question, I then did this

.
.
.
      - id: set-env
        run: |
          AAA=${{ env.A }}
          AAA=`echo -n $AAA | base64 -w 0`
          echo "AAA=$AAA" >> $GITHUB_OUTPUT
    outputs:
      AAA: ${{ steps.set-env.outputs.AAA }}
.
.
.
    steps:
      - name: echo
        run: |
          C=`echo -n ${{needs.job-0.outputs.AAA}} | base64 --decode`
.
.
.

but nothing got printed in the second job