Ah, it's implemented differently.
From InteractUnit:
loc_6F272D:
cmp WoWHardwareEventNum, 0
jz short loc_6F2748
.data:0135EC60 ; int WoWHardwareEventNum
.data:0135EC60 WoWHardwareEventNum dd ? ; DATA XREF: sub_498770+3r
.data:0135EC60 ; sub_4987B0+5Br ...
Set that number to 0 before you call the function.
EDIT: Obviously if you're calling it from a script and not WoWs main thread you'll need to patch stuff that writes to that variable.