If the data is as valuable as you say, you should immediately remove the drive- as in, right now, and keep it in a safe place. Then consult with data recovery services to see what they can offer for SSD drives, with the brand and model information on-hand as that can affect their quote. The more you mess with the drive to try to get it working or "recover" data and the more likely that it will be damaged further or that the data will be harder or even impossible to recover, assuming it isn't already.
From what I can find you would be looking at something like $3,000+ for Data recovery services with an SSD. And that price tag applies regardless of whether data is recovered as far as I can tell.