I'd suggest trying to get some "written" confirmation of the situation (perhaps an email from the doctor's office or the hospital), then turning up at MCO with bags and see if you can get on either flight to LGW tonight. BA2036 is at 1735, and BA2038 is at 2015. Both still have space for sale in all three cabins, so if you explain the situation, show them any confirmation you've been able to get, and volunteer to sit in WT if need be, just to get home as fast as possible, you might find a sympathetic ear.

That assumes that your reference to ex-EU means that you're UK based.

If you're messing about with trying to preserve flying in CW or business, someone will start wondering just how immediate your need is. You need to convey the message that your top priority is getting back to the UK in any seat - if that is indeed the case.