Under GOP Conference Rules, Trump cannot serve in a GOP Leadership Position:
www.gop.gov
Rule 26—Temporary Step Aside of a Member of Leadership who is Indicted
(a) A member of the Republican Leadership shall step aside if indicted for a felony for which a sentence of two or more years imprisonment may be imposed.
(b) If a member of the Republican Elected Leadership is indicted, the Republican Conference shall meet and elect a Member to temporarily serve in that position.
(c) If a member of the Republican Leadership resigns pursuant to this rule, and subsequently during that Congress is acquitted or the charges are dismissed or reduced to less than a felony as described in paragraph (a), such Member shall resume the position from which they resigned, unless the Republican Conference decides otherwise within 10 legislative days.