The exact manner of death is not at issue. The kind of lives lived is not at issue. These individuals may well be canonized, but perhaps not as martyrs.

The killer must be non-Catholic. The killer must hate the Catholic Faith. The martyr must have died specifically for being Catholic.

Numerous examples, including children, took place during the Spanish Civil War at the hands of communists and atheists, during the 1916-37 period of Mexican civil war, murdered out of pure hatred for the Faith.

The individuals you mention may have died “in odium caritatis” - “out of hatred for love”.