What currency you're trying to send?
I just heard that it's incredibly cheap to send SGD and other currencies via Sunway Money. I suppose it's even cheaper to send RM10,000 SGD to SG bank then SGD to IBKR and manually convert paying the tiny fee. Still cheaper than losing RM90 per RM10,000 transferred.
I think they only need to verify your address.
Use your passport to verify identify and your IC to verify address.

I guess CIMB is regarded as untrustworthy by them. Malaysia is famous for money laundering/terrorism financing so I'm not surprised. Try Maybank or other banks.

Edit: Removed personal info
Just an update. My transactions went through. Both Instarem and Transferwise.