No, the Catholic Church didn't ban geography (which I'm presuming is what the statement means by "medieval church"). E.g. after Magellan's trip, the Holy Roman Emperor (and Spanish King) gifted a map to the Pope, which is still in the Vatican's archives. Such an act would have been impossible if geography was banned by the Church. There's also a Vatican Gallery of Maps
from the same century, albeit these are limited to Italy.
The are some late 19th century quotes [mis]attributed to Magellan, trying to paint him as a fighter against [prior] Church canon, but there's no real/earlier evidence he said such things. There were some early middle ages [Greek] Christian cartographers like Indicopleustes, who complained that a spherical earth conception is Pagan, but this concern apparently didn't carry much water in later medieval times, especially in "the West". According to one study most of the medieval Christian "flat earthers" belonged to the Antiochian patriarchate.
If one sticks to a more English-centric view, which I'm guessing is what Jenkins might be more concerned with, I suppose a valid criticism is that some (or even many) medieval maps like the one in the Hereford Cathedral were combining real geographical knowledge with Christian canon elements:
Makers of mappae mundi tried to include all their geographic knowledge, but they also used myths and religious dogma. They included the Garden of Eden and Paradise as well as real cities such as Paris and Antioch. They filled unknown regions with monsters, imaginary countries, legendary kings, and bizarre races of humans.
But since Jenkins himself wrote books about the churches (and cathedrals) of England, he's almost certainly aware of these maps.