Glad I could help.
I double checked which ones by the second where happens, but the one you said is the one where is most noticeable.
It happens barely at: 1:48:42, 1:48:54, 1:49:23, 1:50:34
Slightly: 1:49:11
Noticeable: the one you said at 1:51:09
Maybe by heavily trimming the scene of the keys would work as well. He is supposed to be an Ace with the broom, so you could make it a really fast paced challenge. I did a test with Vr.2. with trimming it like this:
Cut at 1:38:06 when he points at the key and shouts “the one with the broken wing” to 1:38:29 until 1:38:34 when Harry’s hand grabs the broom and keys start going down. Cut until he is already almost catching the key and passing it to Hermione, from 1:39:01 til 1:39:12. Next cut would start from 1:39:17 til 1:39:19 so we see her trying to open the door but avoid again the horrible CGI and the we unite this bit with 1:39:21 where she opens the door and Harry comes in.
This would avoid most of the horrible acting and CGI of this challenge, but keep it for a better, fast paced, plot. Again I did this with the Vr.2.