Why did the Dutch, French & British acquire minor colonies in South America?

The Netherlands mostly was active in the area to hurt the flow of gold and other riches to the coffers of their European enemies, the islands (and coastal forts) they took were a side effect of that more than anything.
In part the same can be said for a lot of what the French and British did in the Caribbean and South America, they were all at war with Spain, Portugal, and each other in various combinations of alliances for centuries and this was reflected in whose buccaneers and privateers attacked whose ships on the high seas, raided which islands and towns.
Later those privateers were largely drawn into the active armed forces of the nations involved, the towns being brought under the control of their respective governments rather than being run by private interests (like the Dutch and British West Indies Companies, and sometimes groups of pirates).
The Surinam was never conquered by the Dutch, it was acquired in trade with the British who sold it to the Dutch in payment for Manhattan Island (which they renamed from New Amsterdam to New York in the process).

France and Britain didn't focus much on South America because it wasn't really valuable territory. they already had access to North America which was a much closer densely forested land in a more familiar climate. They really didn't stand to gain as much by creating a large presence in the area because they had other colonies providing many of the same goods. Managing and controlling colonies is a lot of work and takes a lot of investment especially when they get large, so it requires a massive benefit to be worthwhile, the benefit wasn't there for South America.

In the colonial era, sugar then was comparable to oil now - it was an extremely valuable commodity, and countries sought to produce as much of it as possible. The Guianas had a suitable climate for growing sugar and had been left unsettled by the Spanish/Portuguese, so it was not surprising that they would be eventually conquered by other European powers. Together with their holdings in the Caribbean, they were able to produce sufficient amounts of sugar. There was no need to expand further in South America.

The answer to your question is one of timing, power and the types of colonies.

There were 5 countries that were the main competitors in the global colonization game. The Spanish, Portuguese, English, French and Dutch.

Simply said the Spanish and Portuguese were about 100 years ahead of the rest, Also known as the Age of Discovery. Portugal and Spain, due to their geographic "isolated" location in Europe, made peace with each other in 1411 (Treaty of Ayllón). While the rest of Europe were in constant war-mode Portugal and Spain prospered and were able to explore. They had trade routes and outposts in Africa and Asia already, but they were looking for a shorter eastern route to India. They left most of North America alone and ended up in South America and the Caribbean. The Treaty of Tordesillas divided the world up in Spanish and Portuguese.

The Dutch, English and French came in action too late and had a different purely business economic interest in the area. The Portuguese and Spanish were in it for "Gold and God". The Portuguese and Spanish came as an army with mostly males. They married native and African women, creating the large mestizo and mullatos population we see in Latin America.

The Dutch and French tried and even managed to claim parts of South America. The largest colony was New Holland from 1630–1654, but lacking the military and population backup (and not mixing with the locals) they Portuguese took the area back again.

The Dutch, French and Englished focused more on the Caribbean with their sugar plantations, which were closer to Europe and made them not wanting Brazil back, because the economic necessity was not there.

Suriname was a Dutch Colony which they shared with the English called Guyana. They got total control over Suriname after a trade against New Amsterdam with the English. The other parts were called (British) Guyana. and French Guyana.

More useful information on The differences in colonization: British, French, Spanish, Portuguese, who drew his information from the source: The Great Migrations: From the Earliest Humans to the Age of Globalization (2008)