You can remove a double glazed panel as I said previously.
Please just bloody do it and we can stop with the repeated break the catflap, call the Police/RSPCA, post on Facebook, check the Land Registry posts from people who haven't waded through and read all the other posts saying the same thing or reading the answers.
1.Land Registry was taking 3 months to update before Covid, it probably takes 3 years now.
2.There is a bend in the tunnel where the catflap is so a broom handle isn't going to break it open.
3.Police aren't interested, neither are RSPCA.
4.Owners are not local so unless they have joined the exact same FB group will not see a post. Will also not want everyone knowing the house is empty.
5.If internal doors are shut the cat will not be ale to access other rooms, so may not get any food or water.
PLEASE get into the house and save everyone another 20 threads of the same stuff. Just pop a window, and choose one where the cat is in case internal doors are locked. Or get a crowbar and pop the door lock as I said on the previous thread. If an alarm goes off it won't be a bad thing.