The method I use to collect the preset name of a plugin is by issuing a "Save as..." command from within the plugin GUI itself. That usually open a dialog displaying the current preset's name in text already highlighted (ready to be renamed and relocated). At that moment, issuing a copy command (either via Automator or KM) in order to later on paste it upon saving it as an AU preset.
LogicPro 10.6.2, MainStage3.5.2
MBPro 17", Core2Duo, 8G, OSX 10.12.6
MacPro, Xeon 6Cores, 64GB, OSX 10.15.7
ULN8, MOTU MIDI TP-AV, C4, MCU Pro, KorgNano, Novation SLMkII
AAS, NI, Celemony, Spectrasonics, Korg, Arturia, etc...
PC, iPad3(V-Control & LogicRemote), AtariST(Notator SL), Several vintage gear