I've made a fix for this based on the one @Homelander did for the harrier.
Place attached file in your ..\DCSWorld\CoreMods\aircraft\F-15E directory, recommend you backup your F-15E.lua file before overwriting (I've attached the old/original version too just in case).
NB: Breaks scripts IC
Things that work:
Fixes MK-20 timed fuzes being too long (bug with current DCS version, might get proper fixed at some point)
Airburst fuzes on JDAMs and MK-8x series
Things that don't work:
CBU height of function setting (I guess the ARMT system overrides them)
LGB laser codes
Bomb impact fuzes - they are always instant, delay is ignored
F-15E.lua F-15E.lua.old