Yes, You did wrong!
Its really about how much money you got with your return, but there is no way id split w 5 people left when only 21 people entered, especially when i am chip leader.
You should look at how much money you made when you split compared to how long you played (ie money you made per hour)
If you were chip leader and the blinds were still managable (Most having over 25 BBs left), Then you should have waited until you got down to at least 3 people to offer a split, or the blinds became unmanagable and the tournament became more luck than skill (I.e. Everyone having under 30 BBs left)
Thats generally when i'll take a split, whenever the blinds are unmanagable or if I make a great deal per hour for the time played.
Id say in your case you definitely did the wrong thing, especially because you were chip leader, and because there wasn't much money in the prize pool to begin with, Im guessing only 3 peoiple were to get paid for the tournament and you guys actually paid 5, which isn't good at all.
75X21 = 1575$ you split 5 ways, you all got just under 300$ im guessing with your pay to the casino and other fees. Thats awful payout whne you are chip leader and im guessing you had played for about 3 hours.
If you would have waited until you got down to say 3 people left your split would have been about 500$ each, and with you being chip leader you could have probably waited that one out and then offered a split.
I was in a tournament with under 30 people before and offered a split with a gentleman who was a decent and regular tournament player and he said "NO, its not worth it with so little people in the tournament"
"If there had been more people in the tournament i would split with you"
I am generally in favor of splits especially if the tournament is very long and you are talking about increasing your payout by 1000$ or more just by chopping, then take the 1000$ increase and you wont have to play 3 handed or heads up, But if there aren't alot of people in the tournament, play it out and try to get your moneys worth, especially when you are chip leader.
Good luck in the future.