2002 Prius with C1259 Code

Just purchased a 2002 Prius at a dealer auction with 117k miles. It has a Greentec hybrid battery replacement. Took it to a shop and found out the codes had been cleared by the selling dealer and now shows a C1259 code which the shop says is requiring immediate hybrid replacement.

I would prefer to hire one of you who repairs bad cells as opposed to the $2600 quote I received for a new battery.

What do you recommend?

Thanks and Godspeed,
Ron
Parkview Motor Company