Here´s a new zip packed file, the original also had an unecessary two folder level of packing.
Within this zipfile I´ve replaced the japanese opts, with the english version, and renamed it, so you don´t have to bother about replacing or re-naming anything.
just unzip this folder, and the folder extract will be Load_LWO
Take that folder and place under something like this, depending on your system and where you installed or placed your blender version...
C:\Program Files\blender-3.3.0-alpha+master.12bde317f4c9-windows.amd64-release\blender-3.3.0-alpha+master.12bde317f4c9-windows.amd64-release\3.3\scripts\addons
Not sure how the py cache folders work, don´t do anything with them initially, unless it´s not working the first time, just place that Load_LWO folder in that addon path folder, then open blender and locate that folder, select it..but don´t target folders below, so just select that one and add it, so this is not installed from the zipfile directly.
Then Go to the Testing tab which filters out wether or not the addon is official, community or testing, otherwise you won´t see it installed, from there you should find it and be able to check it, save preferences, then go to import and test any 2015 lwo format.