Quaternion slerp loop exits before equality of quaternions

The loop involves 3 transforms: playerBody, playerHTP and playerVTP which is a child object of playerHTP. I want all 3 of them to have the same rotation which is the rotation that playerBody has. So I created a while loop that slerps playerHTP to playerBody, and simultaneously slerps playerVTP to a local rotation of Quaternion.Euler(0,0,0). It works sometimes but other times it does not work which is why I cannot understand what is going wrong? I guess it has something to do with different cases of playerBody's rotation but I dont understand why different rotations of playerBody are reacting differently. Here is my code:

         while (playerHTP.transform.rotation != playerBody.transform.rotation && playerVTP.transform.localRotation != Quaternion.Euler(0, 0, 0))
         {
             if (playerHTP.transform.rotation != playerBody.transform.rotation)
                 playerHTP.transform.rotation = Quaternion.Slerp(playerHTP.transform.rotation, playerBody.transform.rotation, 5 * Time.deltaTime);
             Debug.Log("HTP rotation: " + playerHTP.transform.rotation + " player rotation: " + playerBody.transform.rotation);
             if (playerVTP.transform.localRotation != Quaternion.Euler(0, 0, 0))
                 playerVTP.transform.localRotation = Quaternion.Slerp(playerVTP.transform.localRotation, Quaternion.Euler(0, 0, 0), 5 * Time.deltaTime);
             Debug.Log("VTP rotation: " + playerVTP.transform.localRotation);
             yield return null;
         }

EDIT: I tried this code and it gave more accurate results but still the same issue happens sometimes:

 float time = 0f;
         Quaternion initPlayerRot = playerBody.transform.rotation;
         Quaternion initPlayerHTPRot = playerHTP.transform.rotation;
         Quaternion initPlayerVTPRot = playerVTP.transform.localRotation;
         while (playerHTP.transform.rotation != playerBody.transform.rotation && playerVTP.transform.localRotation != Quaternion.Euler(0, 0, 0))
         {
             playerHTP.transform.rotation = Quaternion.Slerp(initPlayerHTPRot,initPlayerRot,time);
             playerVTP.transform.localRotation = Quaternion.Slerp(initPlayerVTPRot,Quaternion.Euler(0, 0, 0),time);
             time += 5*Time.deltaTime;
             yield return null;
         }

The issue only occurs sometimes that is why I believe it is something to do with specific values of quaternion rotations. If it was some other part of my code causing it, it would happen everytime.

I also confirmed this with the Debug.Log() that you see. I added the ones in the code and a final one after the loop was over to notify me that the loop has exited. As I expected, when the rotations happened correctly, the loop exited after equal quaternion values being printed (equal for playerBody and playerHTP, and (0,0,0,1) for playerVTP as it was local rotation) , and when wrong rotations happened, the output values were unequal.

This loop is executed when my player enters a trigger and it can enter it at any angle it wants which is why the Quaternions vary based on the current play through. That is the only possible reason I can think of why this happens only sometimes