Elon Musk’s ?public endorsement this week of a potential US$3.5-trillion merger between SpaceX (SPCX-Q) and Tesla (TSLA-Q) has rattled some insiders involved in the discussions, ?who worry his comments could invite shareholder scrutiny and delay the process by ?several weeks, according to a person with direct knowledge of the talks.The disclosure created a “mess” for the process, as it could lead to questions about how well Tesla shareholders’ interests would be represented, the person said. The concerns reflect similarities some participants see with Tesla’s 2016 acquisition of SolarCity, which sparked years of litigation over Musk’s role ?in the ?deal.Musk, who…