That was the version the prosecution gave at the original trial before the police realised they had mixed up the swipe data.
Joanne Williams's testimony has always been that he was "in or about" the area when she returned and heard the alarm, and that he then asked her what had happened and who had been in there.
Nothing in anyone else's account bears out Dr Jayaram's story of the sequence of events, and he has contradicted his own testimony more than once.
They may have entered roughly simultaneously, but he seemed to think she was there first according to her testimony (which never changed)
From the 2024 retrial:
BM: I want to ask you about what happened then when you came back from seeing the family as much as you can help us.
Your recollection, Nurse Williams, is that when you came back, which is round about 03.47 or at 03.47 from the door data, an alarm or alarms were sounding. That’s what you remember?
JW: That’s what I’ve written in my statement, yes.
BM: That’s what you wrote in your statement.
I’m going to go to other parts of the description. You remember Dr Jayaram being present in or about the area when you returned, don’t you?
JW: Yes.
BM: And he was saying things like, “What’s happened? How’s this happened?”
JW: Yes.
BM: If there’s any mystery, again, you made a statement on 10 April 2018, so a lot nearer the time than now.
JW: And I remember him asking me that.
BM: “What’s happened? How’s this happened?”
And in fact you said, “I don’t know, I wasn’t here, I was with the parents.”
JW: Yes.
BM: And he was also asking you who was in the room at the time the alarms went off. That’s something he asked. If it assists —
JW: Yes.
BM: [overspeaking] He did, yes. You remember him asking you who was in the room at the time the alarms went off?
JW: Yes.