First things first, before you ask, P10 and TPA Systems are the 2-prong plug-ins that are used wtih dispatch and emergency services systems. You’re welcome.
Now that that’s out of the way, the answer is simple:
NO. THESE PLANTRONICS ADAPTORS ARE NOT COMPATIBLE WITH LEITNER HEADSETS.
At best we got 1 way sound, at worst, no sound at all. This was thoroughly tested with other Customers using these systems by our intrepid SAM team. The results were not good. Boo!