There is no option to get the admin account that was used by your helpdesk to elevate access while installing an application in device.
However, there is another way that you can use to get the account details only if they had used any of the Entra ID account.
You can check on user device and get the timing of the application which was installed in their device. At the same time, you can check Entra ID sign-in logs for that time and check the account that was authenticated.
If helpdesk has used any of the Entra ID account, then this account would get authenticated again Entra ID. All authentication logs would be tracked in sign-in logs of Entra ID.
Or you can check event logs in the device itself to confirm what was the account that was used to install the application in the device.
Let me know if you have any further questions on this.
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