Yes it does - the part you cite was written because they found it an official act with a presumption of immunity that the government has some chance to rebut. If it had been an unofficial act, there would be no immunity at all.
Here:
"Whenever the President and Vice President discuss their official responsibilities, they engage in official conduct. Presiding over the January 6 certification proceeding at which Members of Congress count the electoral votes is a constitutional and statutory duty of the Vice
President. Art. II, §1, cl. 3; Amdt. 12; 3 U. S. C. §15. The indictment’s allegations that Trump attempted to pressure the Vice President to take particular acts in connection with his role at the certification proceeding thus involve official conduct, and Trump is at least presumptively immune from prosecution for such conduct"
Yes it does - the part you cite was written because they found it an official act with a presumption of immunity that the government has some chance to rebut. If it had been an unofficial act, there would be no immunity at all.
Here:
"Whenever the President and Vice President discuss their official responsibilities, they engage in official conduct. Presiding over the January 6 certification proceeding at which Members of Congress count the electoral votes is a constitutional and statutory duty of the Vice President. Art. II, §1, cl. 3; Amdt. 12; 3 U. S. C. §15. The indictment’s allegations that Trump attempted to pressure the Vice President to take particular acts in connection with his role at the certification proceeding thus involve official conduct, and Trump is at least presumptively immune from prosecution for such conduct"