I have, but mostly they have been ND bonuses from casinos I play at already. I think the only ND new player bonus I've cashed out at was from the Rival casino Vegas Sky, and Rival no longer accepts Canadians. When they launched, they had an especially generous ND bonus, and lots of CM members cashed out. I had played dozens and dozens of NB bonuses before that, and quite a few since.
Over the Xmas season, ClubWorld had quite a number of ND bonuses available for depositing players, I made max cashout of two out of 15 (I missed one, it was NY Eve instead of NY's Day like the other properties), for $250 on both of them.
I've had cashouts from many of Inetbet's freechips, as recently as the past month. They are only for depositing players usually.
There are many free chips out there, but you really need to read Terms and Conditions. Often you are restricted to one per group. Or you need to make deposits between free chips. Most free chips, and certainly all SUB free chips AFAIK have max cashouts, and sometimes require a confirmation deposit.
There's a bunch of shady casinos where you shouldn't even give them credit card detail, or you may spend a year or more of pestering to get a small cashout (think Virtual Group).
Before taking any free chip, do some research on the casino. Consider using a separate email address in case you get spammed to death.
It's not likely to cashout from a free chip. And there are only so many casinos offering them. As I understand from your previous posts, MG and RTG are no longer options for you. You can get blacklisted for taking too many in quick succession as well, as showing no risk of your own funds.
If you do take a ND bonus offer, read the terms and conditions very carefully. There are usually restrictions to the games you can play, and the size of bets you can make.
The amount you've played in a short period of time, you might do better establishing a solid relationship with a casino as a VIP. Many offer loyalty and cashback bonuses, and at your level of play if you stick with one through the bad sessions, you may have your own VIP host.
You seem to like to play long sessions, you might want to consider deposit bonuses. Some are better than others, and you need to educate yourself to tell the difference. If you are going to play 40 hours and break even, you would easily meet the wagering on a deposit bonus that gave you twice the start balance, and have doubled your deposit.
I try not to be critical of people, and you say you have a good job, but 20K plus down in a few months is a heck of a lot of money for anyone. I can't see someone willing to make $18 spins being happy with a $10 ND bonus max cashout of $100 after hours of wagering, maybe. Actually, I've made a few $18 spins in my time, but on lower variance slots than Break da Bank again!
Maybe give up 3 months of online play and just call up a resort in Vegas and ask to speak to VIP accounts. If you transfer a certain amount to the cashier, they will bring you down to play.