There is A LOT to this story that I think is missing.
First red flag,
"According to Frankel’s Tweet, the impromptu haircut was ordered by referee Alan Maloney, who would not allow Johnson to compete with a cover over his hair."
a) Why? Was his hair cover not legally attached to the head gear?
b) No one else on the team had another head gear attached with a hair cover?
c) I don't care how big of a match this is....why cut your hair for a wrestling match [unless the dreads meant nothing to the wrestler]....90 seconds isn't a long time to cut all those dreadlocks.
As a ref, I would do everything within my power to prevent this....like the OP mentioned, a proper full skin check/special equipment check prior to the beginning of the match. Always ask to see mouth guards, hair covers, and knee pads. Yes, sometimes, this kind of stuff can sneak by us, so I get it. When it came to the match. I am wondering if it happened before the match or during the match. It seemed like it would have to come prior to the start of the match.
I don't fully blame the ref, but these coaches must have known. Rules are rules. How do you not have backups of singlets, head gears with attached hair covers. Know your team, know your wrestlers. Kids will be kids.
I wish we got the full story, but I feel like I am left with more questions than I had before reading the story.