Yes. Abraha was a Christian but I have never heard this point stressed in the story of the Elephant. It is related in the Quran, Surat el-Fil, one of the very short suras toward the end of the Quran. According to Tabari and others, Abraha had built a shrine at Sana, a pilgrimage site, and Makkah was a rival place of pilgrimage. His campaign is reported to have had the objective of erasing this rival pilgrimage site. It seems this was mostly about revenue from pilgrims.

The authors of the video you saw seem to impose their peculiar sectarian gripes onto this well-known religious text. It is common enough for religious folks to tweek a source to cause it to say something that it does not actually say. This is reprehensible. Doubly so for self-appointed guardians of piety.

Your comments about explaining religion to children are more interesting than this though. You reminded me of something i read recently about Richard Feynman, who is supposed to have said, “If you can’t explain it simply, you don’t understand it well enough.” There is a four step process for learning called the Feynman technique, which begins with simple explanation of a concept.