Tested with GZDoom g4.8.0
Load this with Doom 2, start MAP01
You'll see two dormant imps. The left one has NOTAUTOAIMED set through ACS.
Aim at the left imp, pull down the console, and enter "info" and/or "linetarget" and note that they can't find the imp.
The imp on the right can be found just fine.
"info" claims actors with NOBLOCKMAP or a height/radius of 0 can't be found, but I never thought it would be the same for NOTAUTOAIMED.