OG's post also misses the mark. England, Northern Ireland and Scotland have differing legal systems, and the cases were also slightly different, so it's not all that surprising that the judgements may be different.
And, for that matter, the fact that it's called a "judgement" and not a "proof" should give the game away: it's always down at least somewhat to an interpretation of how law applies to a given case.
A Scottish court was chosen because the 300 year old law enabled the Scots to forfeit James VII as their king and establish their sovereign right to choose a Government.
The 76 MPs used a case based partly on the Claim of Right Act, passed by the Scottish Parliament in 1689. This tack wasn't available in an English Court.
It matters not a jot. It's still part of the Scottish Constitution and was identified as a tool to get what they (the MPs) wanted which wasn't possible in the UK.
So, one is being informed that the Scottish legal system allows opinions to be expressed as facts and a judgement based on that ? The Scots probably would benefit from examining that part of their legal system again then.
And, again, ZM: what is the point of trying to use an English Court in the Summer when it isn't even sitting?!
Political naivety indeed. There's a legal process to follow: the judges involved are independent; the judgements they've reached may or may not be upheld when it comes to the Supreme Court, but when that decision is made it will have the respect of every party concerned.