I used Entran II for my radiant heat when we built this place in 1993. I ended up in the lawsuit & actually got money....just enough to buy new tubing. I was hoping it would cover labor to remove, replace, but, no. Mine is "staple up" so it's possible to remove & replace. Those with "in the concrete" got more money per square foot, but, again, not nearly enough to do the entire job. Like most any lawsuits, the lawyers made out like fat rats & the people that deserved the money didn't get nearly enough to cover costs of repair. On one hand, yes, I believe you are too late to get anything. On the other hand, sadly, you wouldn't have gotten enough to repair the floor anyway. *sigh*
You see, at this point they look at it like this: It was warranted for 25 years. It's been over 20 years since it was manufactured. If yours failed now, it served it's purpose for over 20 years. They pro rate it and would only owe you 20% of the cost. Even if you got money it wouldn't be enough to buy three cheeseburgers.
It sounds like yours is in the concrete. Most people in this situation end up going with baseboard.... not an easy job at all, but, far less than a new floor. Some go with a "on top of the floor" radiant. It's more expensive by far and you lose some headroom.