coincidence maybe lightining would'nt affect hdmi connections unless the tv was connected to an aerial/satellite dish and received a shock or partial shock and damaged the tv i'm guessing that the scart connection was not used during the storm and the vga is from your pc/laptop
if the other devices are ok i would'nt have thought that the ac spiked as they would be damaged as well everything being on a ring main if the tv works with no connections other than aerial or dish then it possibly isn't the tv is this a new setup or an existing one are the hdmi cables ok
I have now removed the back cover of he TV and removed, made a visual inspection on the main circuitboard with all the connection and found nothing visually damaged. So my best guess now is that a IC handling the hdmi interfaces is internally damaged, maybe you are right there is a switch in front of a single hdmi input.
I have sent a question to a service center in Sweden to see how much a new CB will cost.
To send the TV for check will cost ~€90 adn they will probably come to the same conlusion that the CB needs to be replaced, don't think they replace ICs on a PCB.