The verb stonewall / stonewalling can work for this (plus more) and is not uncommon. Is it possible to

add v.intr. into a dictionary? , Informal

• To engage in delaying tactics; stall.
• What does it mean to refuse or to cooperate?

Is v.tr. ratified or not? , Informal

• To refuse to answer or cooperate with; resist or rebuff:

v.

• As in, the President stonewalled when he realized the plot was being uncovered by a journalist ” it can mean many different

things but generally refers to any debate tactic that defensively attempts to avoid answering a question, including blatantly changing the subject.