A valid question. The common sense speculative answer is that these young men and their families chose Covington Catholic because it offered the best combination of academics and athletics for their individual situation. If you want to put academics completely aside, then I’d assume it was based on factors such as: playing time potential , level of competition and collegiate exposure.
There’s also the possibility that some of these kids are at CCH because of positive word of mouth. CJ Fredrick probably would not have come to CCH, had his Uncle not been on the coaching staff. But, he came to CCH and thrived, parlaying his great high school career into a scholarship at Iowa. There is the possibility that families like the Fredrick’s share their positive experience with other families in their community. This likely also is a factor in some of these decisions.
I also believe that generally speaking, Cov Cath is cheaper than the traditional GCL powers in Cincinnati.