I would claim the ticket reimbursement in one claim, cross referencing it to a separate claim for right of care. Don't forget to add in for any food, drink, travel costs to the hotel and communication costs. The reason being that the latter is not going to be difficult to process and you should get that quite quickly. The reimbursement of the OLB-STR may be more problematic and may take longer to resolve.

The train ticket - well ask for this in the hotel claim, it may be covered by BA, but strictly speaking BA can make you sit it out in a hotel until they can get a flight sorted for you. By all means mention that by taking the train you were limiting BA's costs in STR. If they don't cover it, then that aspect can be pushed to Amex.

More details about this whole area can be found in the EC261 thread, in the Dashboard.