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Never heard of somebody "cleaning a fuel filter", why go through the effort of removing it and not replacing it with a new one?
Another thought related to hot starting is one or more bad ignition coils.
Did the mechanic decide to replace all those parts chasing this problem?
Page 6-65 shows you have a relay for the left headlight, the right headlight and the running lights. Check the markings on the relays with other relays in the box, if they have the same markings, switch them and see if the problem moves with the relay...