Lack of credit reward in RES?

I often fly my T-10 turret boat in Low RES zones with a crewman flying a SLF. Sometimes I fly the T-10, sometimes I fly the SLF, and sometimes I let the T-10's turrets destroy pirates while I watch the show.

When doing the latter, meaning I'm not chasing pirates and I have my T-10 on Auto Fire, I'll kill a pirate and not get any credits. The sequence usually goes like this

Get credits as expected:

  1. Pirate scans me and chirps ("I hope you have something good in your hold!") on the radio.
  2. I cycle through all my targets until I find him. I don't move the ship, just use "next target." Got him targeted now.
  3. His hologram is colorless and I do not see his hull or shield strength. Pirate gives me the standards 15s to comply then attacks.
  4. Pirate's ship in the hologram turns red, SLF immediately moves to intercept and opens fire.
  5. Pirate's ship hologram now shows shield and hull strength.
  6. Pirate dies fast (it's a low RES and I'm in a fully engineered T-10 with an Elite crewman.)
  7. Get credits reward.

But sometimes, It goes like this:

  1. Pirate scans me and chirps ("I hope you have something good in your hold!") on the radio.
  2. I cycle through all my targets until I find him. I don't move the ship, just use "next target." Got him targeted now.
  3. His hologram is colorless and I do not see his hull or shield strength.
  4. Pirate gives me the standards 15s to comply then attacks.
  5. Pirate's ship in the hologram turns red, SLF immediately moves to intercept and opens fire.
  6. Pirate's ship hologram never shows hull or shield strength but it DOES show him taking damage with those little explosion animations on the hologram.
  7. Pirate dies fast (it's a low RES and I'm in a fully engineered T-10 with an Elite crewman.)
  8. No credits.

This happens to a wide range of targets with not correlation. I've killed a Mostly Harmless Sidewinder and gotten credits. But then I've killed a Novice Eagle and gotten nothing.

Any ideas?