It's interesting that a LANDesk employee tell you that OSD is antiquated and going away. Well, since you likely have LD9.5 or 9.5sp1/sp2, OSD is still a supported feature within those versions. Simply contact LANDesk support, and get some assistance. The log file on the core is a good place to start troubleshooting. C:\Program Files (x86)\LANDesk\MangementSuite\ldmain\log and look for a job that looks something similar to: CJ-OSD-Capture_Windows7_64_IMG_3.3-0-06302014-120602.log (this was one of mine as an example). Sometimes the error code in there will clue the technician what to look for, other times not so much.
One thing that has bitten me over the years, is making sure the drives are mapped properly to H: and I: The concept is, if the tools and the image path are not mapped, it can't execute the image script.
Is the service account that you are using within the OSD script locked out?.
Put a ; at the end of the OSD script, on the last line of the script, to halt the reboot. such as this: ;REMEXEC29=ldrun reboot, timeout=2
this will keep it from rebooting, then you can within WinPE, do some troubleshooting.
You'll spend about 2 hours or so troubleshooting with LANDesk, but I bet you find it to be a really silly setting that caused it. Sometimes, you'll go line by line in the script until you find what is the problem.