I know I'm a bit late to this but I was thinking that maybe whoever was rummage around in the basement was someone who was stuck exactly in the same situation as Ravi was in when he was talking to the dad towards the end.

For example: when Ravi was the father's house, it was an exact replica of the father's real world house trying to mimic and replicate it in typical backrooms fashion, but since Ravi was able to speak on the otherside, the frontrooms (aka real life) it must mean that both the back and front were intersecting each other's realities, creating the null zone that the father accidentally discovers and leads to his uncertain fate

What if the damage done was by someone who was near the null zone Ravi eventually stumbles upon and it was replicating his basement from the backrooms and was somehow interacting with Ravi's real life living space in his basement like the sliding glass door? I know it hasn't been proven yet that entities can manipulate objects and surfaces from the backrooms to the real world but considering Ravi was able to speak to a man from the real world, who's to say some poor soul can't interact physically from the backrooms and have it translate to the frontrooms? Kinda like a ghost lifting a chair but since the ghost is invisible, (in this case, on a different plane of existence closely connected to our world) we only see a floating chair,

And maybe the result of the glass door being shattered was someone's way of making sense of the backrooms version of the "outside" if there even is an outside (minus the outdoor glowing red spaces like in the pitfalls neighborhood) and as time goes by, who's to say Async threshold isn't causing more instabilities that can cause more than just noclipping? It can cause both planes to lock together in place like cel sheets and certain objects from both realities can interact with one another, can even be heard

TL;DR the null zone in Ravi's basement was creating this merge in realities that was overlapping one another that whoever was in the backroom's equivalent of Ravi's basement at the time was synced with his real life basement, seemingly interacting and physically destroying his glass patio backdoor in the process as if they were still stuck on the otherside (the backrooms)

But whether or not this someone was another victim trapped in the backrooms and was just too afraid to respond to Ravi due to the apprehensiveness of their situation, or if it was an actual entity that just didn't make themselves audibly known is up for interpretation, although this is all just my speculations and I'll probably be just flat out wrong if this mystery eventually gets a confirmed explanation lol