Ejaculating is defined as ejecting semen or sperm. I'm not sure what the proper terminology would be for how it works in reptiles, I just didn't want anyone to get confused.
As far as the subject of the post is concerned, I will agree with you that the sperm plugs do not actually fertilize the follicles, however, regeneration of sprem plugs should give you a pretty good estimate at how fast they regenerate sperm(i.e. how soon they can copulate with any guarantee of actually being successful at procreation). I hope that wasn't too confusing.