If I understand correctly (correct me if I am wrong), in DxD, timelines are created at different events, and every different event has its own timeline. Even possibilities or impossibilities has his own timeline.
For example, in High School DxD light novel, during Loki fight where Issei used his ability on Akeno and connected to the Fairy of the Goddess of Breast, and got a blessing. But in the anime Season 3, during the Loki fight, Issei didn't use his ability on Akeno.
And there are timelines where Freed Sellzen is still alive (Twitter timeline), but in the anime and light novel, he is dead.
Also, there is a "dream" Freed Sellzen saw, where he tries to kill Asia, but Kiba killed him, which is the anime and light novel timeline (I think maybe in DxD, dreams are actually different timelines).
Rias in Wonderland is a different timeline, where the Bible doesn't exist.
Now, the thing is, the Breast is used as an example for the timeline by MasqueTLDF, which follows this:
Issei gains a power-up from the Breast in a different time than originally (light novel) timeline, creating a new timeline, the anime timeline, where a few different events happen, which originally didn't happen in the original timeline, or already happened in the original timeline, or later happen, creating a timeline.
And for Telos Karma, Telos Karma has the ability to make possible or impossible things happen, and there are countable infinite possibilities or impossibilities.
The thing Digital_Franz is rejecting is that Telos Karma creates new timelines, which may be right, because Telos Karma has the ability to forcibly make things happen, which becomes the original timeline for its users.
But if Digital_Franz is rejecting that there are infinite possibilities or impossibilities that have their own timeline, which are different from the original timeline (light novel), then he is wrong here, because, as you can see in the example, there are timelines where Freed Sellzen is still alive, which is a different timeline than the original timeline (light novel). And more example
So, I think DxD has infinite timelines with infinite possibilities or impossibilities, where different events have happened or not happened, as their own timeline.