VERY VERY Interesting comment by our friend Mufti Mangera.
He mentions his experience of burning cloves and/or chilli for evil eye (on kids) and I always thought it was biddah or even shirk. Amazing :(
I think your confusion is coming from inability to distinguish between worship and (cure to) Illness. When someone has fever they (should recite) Al-Fatiha 7 times and drink Zamzam but it is also permitted to use contemporary medicine which is not Haram.
IF there are elements of Haram, they will need to be looked at in terms of scope and breadth of illness.
Magic or Jinn possession is a sickness. There are Sunnah recommended remedies (which are superior) but then just like any other sickness you can methods which are not Haram.
Medicine and methods of cure are always based on personal experience, for example a friend of mine finds smelly salts extremely effective in patients who have been affected by Jinns. I have seen this in action and I am not sure if the patient is being impacted due to the pungent odour or the Jinn is being affected, either way the patient definitely jolts back to consciousness.
In acts of worship, nothing but suggestive text is permissable.
This cannot be undone and I am sure it will be greatly appreciated.