Your agent is correct. Pay for remaining excess and send for reimbursement is the correct way.

Different policy, different insurance have different coverage, and different assessment. You cannot expect other insurer to 100% cover all the remaining excess.

Don't even think about splitting the hospital bill because it will complicate things - some thing in the bill will raises some questions, some inconsistencies because the billing people did a sloppy job that will further delay your final GL.

Alternatively, why not just request GL under your personal insurance?

Yes of course. This is relatively easy. You get a GL for your personal insurance and then pay-and-claim the rm5k deductible from your corporate cover. It's also much easier on the wallet as you only need to bear the deductible amount.

In TS case, why not go for his personal insurance since the estimated expenses going to exceed rm50k? Seems rather silly.