Laski matters less as a person than as a demonstration of how this kind of work was funded. Renaissance angelic magic and alchemy were expensive. They required a household, travel, apparatus, materials and above all uninterrupted time, none of which a scholar without means could supply, so the practitioner had to be useful to somebody who could. What a patron bought was rarely a doctrine. It was a prospect: gold, an heir, a favourable outcome at court, or advance knowledge of events. The relationship lasted precisely as long as the prospect stayed plausible.
The record shows the pattern repeat. When Laski's resources failed, the party attached itself to Vilem Rozmberk and settled for a period at Trebon in Bohemia, where the alchemical work carried on under a new sponsor. The scrying sessions continued either way, which suggests the material was not being produced to order, but its survival depended on somebody paying for the room it was produced in.
Almost everything known about Laski's part in this comes from Dee's diaries and from manuscripts printed long after both men were dead. That is a narrow evidentiary base for someone who was a real political figure in his own country, and it is worth stating plainly: the atlas holds him as he appears in another man's papers.