Klcc can reedem cash voucher kah?

Hi, need some opinions from the expert here.  I’ll be charging one lump sum (medical bills from IJN) to my credit cards later this week, estimated to be around RM40k +/- RM5k.  Does IJN accept AMEX payment? 

Beside 5X treat points (it’s on weekday, so no 5% cash back) from AMEX, what other cards that will provide the most benefits/returns for this lump sum charge?

Credit cards that I owned:
- Maybank 2 Cards Platinum  (5X treat point for AMEX)
- UOB One Platinum (0.3% cash back, thinking of charging RM20k to this card to get the Nestcafe coffee machine, but not sure if I’ll ever use it)
- UOB Visa Infinite (unsure of the benefits)
- RHB Visa Signature (I think it give 0.5% cash back)
- Public Bank Visa Signature (not sure the value of the points, no cash back for this category)
- OCBC Titanium Card (pretty much useless now)
- Standard Chartered Visa Platinum (not much benefits)

Hi all, when i look at my transaction history, i realise i was double charged when i bought my groceries at AEON. I am very convinced that i was double charged as i incurred the same cost on the same day at the same place.

Guys, how to fix this? complain to maybank or aeon? transaction was on 27/5/2015. is it too late?

Thanks for advices in advance