Productsigned Mac app not installing in computers that are not mine

Question

I have a Mac app which I have signed using the 'productsign' command from the terminal

productsign --sign "3rd Party Mac Developer Installer: My company (dasdfjkaj)" InstallerUnsigned.pkg InstallerSigned.pkg

productsign: signing product with identity "3rd Party Mac Developer Installer: My company (dasdfjkaj)" from keychain /Users/me/Library/Keychains/login.keychain
productsign: adding intermediate certificate "Apple Worldwide Developer Relations Certification Authority"
productsign: Wrote signed product archive to InstallerSigned.pkg

I then ran the assess command

spctl -a -v --type install  InstallerSigned.pkg
InstallerSigned.pkg: accepted

I also checked the signature

pkgutil --check-signature InstallerSigned.pkg 
Package "InstallerSigned.pkg":
Status: signed by a developer certificate issued by Apple
   Certificate Chain:
    1. 3rd Party Mac Developer Installer: My company (dasdfjkaj)
    2. Apple Worldwide Developer Relations Certification Authority
    3. Apple Root CA

When I run the installer from my machine (with Gatekeeper set to "Mac App store and identified developers") it runs fine. It also installed properly when I downloaded the same pkg after I deployed it to my website.

But... when I download the pkg in another machine it fails to install. It does not recognize my developer ID. When I run the spctl command on the failed machine, I get

spctl -a -v --type install  InstallerSigned.pkg
InstallerSigned.pkg: rejected

Does anyone know why this it runs fine on my own machine but fails when the pkg runs on another machine? I am all out of ideas really :/

EDIT: This is what I get when

spctl --list --type execute
3[Apple System] P0 allow execute
    anchor apple
4[Mac App Store] P0 allow execute
    anchor apple generic and certificate leaf[field.<I removed this>] exists
5[Developer ID] P0 allow execute
    anchor apple generic and certificate 1[field.<I removed this>] exists and certificate leaf[field.<I removed this>] exists
7[GKE] P0 allow execute [(gke)]
    cdhash H"<I removed this>"
10[GKE] P0 allow execute [(gke)]
    cdhash H"<I removed this>"
14[GKE] P0 allow execute [(gke)]
    cdhash H"<I removed this>"
15[GKE] P0 allow execute [(gke)]
    cdhash H"<I removed this>"
18[GKE] P0 allow execute [(gke)]

Answer 1

Certificates Matter

These are the certificates you will need to use together for codesigning:

• Developer ID Installer

• Developer ID Application

  • 3rd Party Mac Developer Installer (usually only used for the AppStore apps).

The "Developer ID Installer" certificate is what you would use if not submitting to the AppStore. For codesigning portions specifically, you need to use the "Developer ID Application" certificate.

Apple Developer Codesigning Workflow Guide