Serious question here ... but how does being on one timeline vs. another dictate what form Ganon should be regenerating as? Why can't he regen into whatever the devs want him to be? How would a timeline dictate what he's allowed or not allowed to regenerate into?
Just being honest here, but it sounds like your "point" is based simply on what you think should happen ... and doesn't consider that the form that Ganon may or may not take on, or resemble, etc. is entirely devoid of connection to a timeline.
Throughout the history of Hyrule, Ganon mostly gets resurrected when slain by Link. Resurrected as in bring brought back to life as opposed to being reborn into something new. If Ganon was being reincarnated everytime he was defeated, he would be able to take any form he wanted without disorting the timeline with his different appearences. However because Ganon is being
resurrected throughout the timeline, his original body is being brought back to life and is not being reborn into a new being. This is the case for the DT as it's the same Ganon that returns after every subsequent title he appears in. He resurrects in OoX, ALBW and before LoZ. There has only ever been one case where Ganon reincarnates, and that's in Four Swords Adventures on the CT.
In Calamity Ganon's case, for a DT placement to work, Calamity Ganon would have to be a new reincarnation of Ganon from the DT, however it's hintied in BotW that Calamity Ganon is a Ganon we've seen before as Urbosa mentions how Calamity Ganon once took the form of a Gerudo. Given how Ganondorf no longer exists in the DT and Calamity Ganon is not a reincarnation of Ganon from that timeline, A DT placement is looking less likely.
But even if this is the CT, it still can't be TP Ganon's human form, as TP Ganondorf was reincarnated as a new Ganon in FSA, and that one shows no signs of returning to his human form anytime soon.
And you can't argue that BotW is inbetween TP and FSA, because recent creator comments have said it's at the end of one of the branches.
For the record, i'm not trying to argue that BotW takes place on the CT. I actually stated in an earlier post that I don't believe BotW fits anywhere in any of the 3 timelines. BotW is like Hyrule Warriors where if you put it down one timeline, it would create a huge contradiction for another timeline. The only difference is that Hyrule Warriors is non-canon whereas BotW Is, so BotW has to fit somewhere on the timeline.
I strongly believe that BotW cannot be down any of the 3 branches after OoT for many reasons: No mention of the Great Flood, Calamity Ganon's resemblemse to Ganondorf, The Zora Monmument talking about the AT events of Ocarina of Time etc. Anything timeline related that is in this game seems to contradict another timeline which makes even a likely placement unlikely.