Is it permissible to dispose of financial trust assets in an unstable work environment to reclaim rights when there is a fear of their loss, knowing that the questioner was ignorant of matters of lawful and unlawful during his youth?

What you did, disposing of the trust and selling it before the state took over the companies, is a betrayal of trust, and you must repent and seek forgiveness. If you had a right against the company owners that was equal to or less than the value of the trust, then there is no blame upon you if this was the only way to obtain your right. However, if the value of the trust was more than your right, then you must return the excess to the company owners if possible; otherwise, give it away as charity on their behalf. Similarly, if the company was public, then give away as charity whatever exceeded your right.