Moss, Meindaerts arrived in Ireland in the late summer of 1716 and was arrested on suspicion of being a Jacobite spy, avoiding imprisonment by convincing an officer familiar with Louvain that he was a student at the university there.

At the time, 52 parishes acknowledged the jurisdiction of Meindaerts: 33 in the Diocese of Utrecht, 17 in Haarlem, one in Leeuwarden, and one in Nordstrand, Germany.

On 2 September 1742 he consecrated Hieronymus de Bock as Bishop of Haarlem, a see left vacant by the Roman Catholic Church since 1587.

The consecration was denounced by Benedict XIV, and Meindaerts responded with a letter that was translated to French, Latin, Italian, Spanish and Portuguese.

In 1763, Meindaerts convened the first synod in Utrecht since 1565, for the purpose of condemning the work of Pierre Le Clere, a French subdeacon living in Amsterdam.