Agreed, I don’t recall any evidence in any of the trials re the communication trail during the June trip. Two thoughts come to kind:
1) Maybe there was nothing out of the ordinary on the trip in June and the reason for the ‘high’ call volume on the July trip was because the first trip failed and Donna wanting to be more ‘hands-on’ OR simply just more eager to get ‘real-time’ information. Thus the 'flurry' of calls on the July trip.
2) Maybe there was a decent amount of calls between Charlie, Katie & Sigfredo on the June trip BUT Donna & Wendi were not part of the communication trail. In that case the prosecution would not want to highlight the call / communication details from the June trip because it would be beneficial to Donna & Wendi’s cases.
I would imagine that WA and DA would not have been able to help themselves. So reckless and impulsive. As the plot fell apart the calls would have increased. There would have been a high degree of stress, anxiety and intensity.