The autopsy report for June states fragments were recovered in respect of GSW 2. It makes no reference to any bullet. Fragments and a bullet were recovered in respect of GSW1. It seems to me the bullets found in June's pillow are more likely to pertain to the GSW's she sustained to her ear/head and neck whilst her head was on the pillow as opposed to her forearm. It's possible fragments lodged internally with the rest of the bullet exiting. I will have to look at the weights again. I can't remember. Must be my age/hormones 
How is it possible to say for certain which exited bullets pertain to which wounds? Dr Vanezis states he didn't know the sequence of shots.
PV/5 is the only fragment Vanezis recovered which was not a unique bullet fragment. It was a small portion of the bullet fired into Nevill's lip or jaw. It's the only tiny fragment he wasted time to recover and label as an exhibit. All other bullet fragments he recovered were the largest remaining fragment from such bullet.
Fletcher's report helps detail what body parts they were recovered from. That in conjunction with the autopsy report is what I used to piece together what I posted. The level of detail with the twins is insufficient because he didn't number those wounds and give enough detail to match them precisely to each wound. You can only do totals, especially since he recovered nothing at all from one bullet.
Autopsy quotes:
1) "recovered from base of left side of skull"
2) "recovered from the left side of the base of the skull"
3) bullet exited thus no bullet recovered
4) bullet exited thus no bullet recovered
5) "bullet was recovered from between T3 and T4"
6) "lower aspect of the body of T9, from where the bullet was recovered"
7) bullet exited thus no bullet was recovered
So according to his autopsy report he recovered bullets from 4 wounds while 3 exited and were not recovered.
His November report which details his exhibit list identifies the 4 bullet exhibits he recovered from June and it is sufficiently detailed to be able to figure out which bullet goes to which wound without even needing to consult Fletcher's report:

There were only 3 bullets not recovered from her body. One entered the bed after exiting her knee. The other 2 ended up in her pillow. The 4th bullet in the bedroom was associated with Nevill's graze wound.