I do not know much about Sir Thomas Dale, but he does appear to have had some contact with James I. This would indicate that this was in England, for had it been in Scotland he would have been referred to as king James VI. I think king James knighted quite a lot of people in 1606, following the union of the crowns of England and Scotland. Thomas Dale appears to be one of them.
This is what I know:
Sir Thomas Dale (d. 1619), soldier and administrator, is of unknown parentage. Given his letter to the states general (1618) which boasted of thirty years' employment in the Dutch cause, he was probably born around 1660. I have seen a reference to him being baptised in 1659, but if this is known to be true, I would have thought the place would be known, and details of his parents also known. He was probably a common soldier in the earl of Leicester's expedition to the Low Countries (1588).
Shortly before he left England (March 1611) Dale married Elizabeth Throckmorton (d. 1640?), granddaughter of Sir Thomas Throckmorton, and a distant relation of Vere; they had no children.
He died of the flux at Masulipatam, India on 9 August 1619. He was buried there.
I have details of about 20 Edward Douglases, but none as early as the 17th century.
I do have an unknown Douglas who married a Miss dale about 1820 (as a guess), daughter of Rev George Douglas and Mary Mellis, who were married in Aberdeen in 1799.
The more information you can give about the people you mention, the more chance there is of someone else connecting with your family.
Dates and places of births, deaths and marriages all help to place families.
Professions also help.
'My great-grandmother mother was a Douglas from Montrose' does not give many clues to follow up! But a bit of flesh on the bones makes further research possible. But if we are told who she married, what his profession was and where the children were baptised, then we can get to work.
Maybe it is time to update the information in your profile?