Question about getting 3 Endings in one NG+ run

So, probably gonna have some spoilers (obviously), but I was wondering if it would be possible to get 3 endings in a run of NG+? And if so, how quickly people think it could be done? (obviously only doing what's required and rushing through)

I just beat the game for the first time, got the "true ending", and the last 3 achievements I need are the other 3 endings... well, and the Lotus Pond shrine (what a stupid Shrine spawn), but apparently getting that shrine and not all 50 again should trigger that achievement.

From what I understand, I could play the game up until the storyteller "point of no return" (making sure to talk to Red Clan lady and doing the two questlines of Fang and He), make a backup-save, then get the Bo Magus ending

After that, reset, and play again until it's time to give the chisel... another backup save, then give the chisel and go beat Obsession of Madness, get ending, reload.

Then, it would be keeping the chisel, and going to beat the final boss. Not beating Obsession to get the rings combined (or not even getting the rings at all), would be the final ending, right?