No. He is wrong; Fr. Garrigou-Lagrange basing his reasoning on Billuart, explains in his treaties De Verbo Incarnato (pg. 232) explains that “a heretical Pope, while no longer a member of the Church, can still be her head. For, what is impossible in the case of a physical head is possible (albeit abnormal) for a secondary moral head. The reason is that whereas a physical head cannot influence the members without receiving the vital influx of the soul, a moral head, as is the Roman Pontiff, can exercise jurisdiction over the Church even if he does not receive from the soul of the Church any influx or interior faith or charity.”

Billuart affirms that “According to the more common opinion, Christ by a particular providence, for the common good and the tranquility of the Church, continues to give jurisdiction to an even manifestly heretical pontiff until such time as he should be declared a manifest heretic by the Church”- Billuart, De Fide, Diss. V, A. III No. 3, Obj. 2.