Looking at that case, the court said (before that list):
"It is clear from the authorities that a provision in a statute prohibiting contracting out does not prevent parties from lawfully agreeing to settle or compromise claims based on the statute. There is, however, often a subtle but substantial difference between a genuine bargain to settle or dispose of a claim, which is lawful and enforceable, and an attempt to exclude or limit the Act, which is void and of no effect. The case law indicates that the following considerations are relevant in distinguishing the former from the latter: - ..."
There is no legal requirement for a settlement agreement to be reviewed by a solicitor or a union rep. All of the factors listed do not all have to be adhered to to the letter in order for a settlement agreement to be enforceable. The fundamental requirement is that the bargain needs to be properly negotiated and that both parties fully understand their rights and entitlements. There is also no legal requirement for a company to pay for legal advice taken by an employee in negotiation of a settlement.
OP, however, seems happy to sign a settlement and seems happy to sign away his rights under the UDA at any rate. Without knowing anything else about OP, it's impossible to comprehensively assess his/her rights and the particular rights s/he is waiving. If OP does fully understand these rights and has freely negotiated the settlement, then there is no legal requirement for the settlement agreement to be reviewed by counsel/solicitor/union rep to be enforceable. That's not to say that it's not advisable for OP to have such a review, but that the lack of a review in and of itself won't make the agreement unenforceable.
Sprite