Very clever, but the engenious group is just ridiculous

partial anagrams is a bit of stretch

Thought anagrams of partial words was stretching a bit!

Not sure why but this one marked my connections as being correct when I left the answer box blank.

The answer to Squid's point is that the setter probably put a comma after the last word fragment in the list of acceptable answers, which is not accessible to the solvers and is completely separate from the explanations which we can see. The comma effectively means "or" so a blank answer gets accepted as correct since nothing follows the comma.