The current rules are if you default all 5 courts in a match you default all matches for the entire season.
The 2 captains that got together were not very smart in planning this out. They still could have lost 5-0 by actually playing the match and have one team put out the weakest possible line up and maybe just default a line or 2.
I have seen cases where it was important for a weak team to get a certain number individual wins in the final match of the season in order for another team to get to playoffs. The captain offered the other captain some players he got from his club and one he found off craigslist (lol) to play in the final match to make sure they got enough wins.