What make and model is the client PC? I would check that there is no RAID enabled in the BIOS and WinPE can have issues with that.
If no RAID then you are going to have to find the storage controller drivers to add to the WinPE image. What version of Ivanti Endpoint Manager (or LDMS) are you running?
Find your WinPE version from here About Windows PE versions used in Ivanti Endpoint Manager
How to add driver help here How to add drivers to WinPE for Ivanti EPM OS Provisioning
There is a setting you can enable in the later version of IEM to allow UEFI PC's to PXE boot without a task assigned. This can be found under PXE boot options
