Their attempt to explain it involves a mysterious shadow object that is opaque enough to block the moon but completely invisible at all other time, despite being relatively close. With no attempt at an explanation of what it is, where it came from, or why its there.
Just like ptolemy's geocentric model forcing circles upon circles to explain planetary retrograde motion, bad models make illogical and unnecessary adjustments to force data that doesnt agree with them. This is clearly wrong.
Speaking of ptolemy's model, his retrograde planet problem seem like it will be a problem for flat earthers too. I wonder if they have an explanation for them too.