Waft Emitter (Raids) questions. Needs recharge? Building location local to creature required?

[Accel Lex]

I tried the Raft Emitter three times (loaded save each time) and it didn't work well either.
The first two I did it from the Red Tree to spawn red ants, so I figured mabye they don't spawn anywhere and need to make the physical trip from where they naturally spawn.
The raid notification sounded, but I was just waiting until they gave up. The second time I rushed to the location it said they were at, but they gave up before I reached it.
This led me to think it needs to be placed in an area nearby.

So I went to the top of the termite cave, placed a Waft Emitter at one of the corners of that location, and the icon showing where they were at was under the porch. I figured mabye they didn't respawn from when I killed them in their tunnels, so this led me to believe you can't activate multiple Wafts in a row without them having time to respawn, since I placed the Waft so close to the hole to go inside the termite den from above.

I place enough creature parts to fill up the bar.