I'll transcribe the exact testimony that I am referring too:
Prosecutor: When the defendant actually separated himself from his child and got on the phone, did he appear to be per the witnesses, talking on the phone?
Stoddard: Yes.
Prosecutor: Did you talk to officers who actually encountered him?
Stoddard: Yes I did.
Prosecutor: What did they say he was doing on the phone?
Stoddard: He stated that he was telling someone on the phone that his child had died.
Prosecutor: Now, when you spoke to the defendant, what did he say about actually speaking to somebody on the phone?
Stoddard: He stated that he had not gotten anybody on the phone.
Prosecutor: Have you reviewed preliminarily his phone logs?
Stoddard: Yes I have.
Prosecutor: What did those reflect?
Stoddard: They reflected three phone calls.
Prosecutor: What was the first?
Stoddard: First phone call was to Leanna. Um. It looked like it was a missed phone call. The second phone call was to Home Depot Corporate Center. Um. Their main number. Um and there was a third phone number and it was the same one, it was to The Home Depot Corporate Center. And it appeared that this phone number went through and on his records it said six minutes worth of conversation.
Prosecutor: Were you able to track back where that would have gone too? This call to The Home Depot Center?
Stoddard. We did.
Prosecutor: Okay, and where would that have been?
Stoddard: It went back to Toddler Room Five at Little Aprons Academy where Cooper attended school.
Prosecutor: So you have phone records suggesting that he was on the phone for five or six minutes...
Stoddard : Correct.
Prosecutor: You have the officers stating that he was actually talking to somebody on the phone.
Stoddard: Correct
Prosecutor: Did you confront him with this when he said that he actually was not talking to anybody?
Stoddard: I did.
Prosecutor: And what did he say?
Stoddard: He said he wasn't talking to anybody on the phone.
Minutes 12:00 to 13:50
https://www.youtube.com/watch?v=A-tiBT_0nNg