The official is correct to issue both a technical foul to A-1 for removing his/her jersey on the court after being disqualified and also an indirect technical foul to the head coach, as the head coach is held responsible for the actions of all team members, including disqualified players.
In basketball ruling, when a player, in this case A-1, commits his/her 5th personal foul, they are disqualified from the game. The player should leave the game floor and take a seat on the bench without creating any additional disruptions. However, if A-1 removes his/her jersey while still on the game's court, it is indeed disruptive and unsportsmanlike behavior which can be sanctioned with a technical foul. Therefore, the official is correct to issue a technical foul. As for the indirect technical foul issued to the head coach, typically, the head coach is held accountable for the conduct of all team members, including substitutes, disqualified players and all other bench personnel. As a result, when a player who is no longer eligible to play receives a technical foul, that technical will be charged indirectly to the head coach. So, the official is also correct in issuing an indirect technical foul to the head coach.
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