Pidgin and creole (language) are concepts that have some similarities but don't fully overlap.

"Creole" has colonial overtones. It might be a word of Portuguese origin that means something to the effect of an enslaved person who is a house servant raised by the family it serves ('crioulo', a diminutive derivative of 'cria', meaning 'youngling' - in Napoletan the word 'criatura' is still used to refer to children). More well documented is its use in parts of Spanish South America, where 'criollo' designated South Americans of Spanish descent initially. The meaning has since drifted in different South Americans countries. Nowadays it is used to refer, amongst other things, to languages that are formed by the contact between the languages of colonial powers and local populations.

As for the relationship of 'creole' and 'creosote' the only reference I could find is to 'creolin', a disinfectant derived from 'creosote' which are derivative from tars.

Pidgin is a term used for contact languages that develop between speakers of different languages and somewhat deriving from both, and is believed to be a word originated in 19th century Chinese port towns. The word itself is believed to be a 'pidgin' word, in fact!

Cajun is also a fun word, because it apparently derives from 'Acadiene', the french word for Acadian - people of french origin who where expelled from their colony of Acadia in Canada. Some of them ended up in Louisiana and the French Canadian pronunciation "akad͡zjɛ̃", with a more 'soft' (dunno the proper word, I can feel my linguist friend judging me) "d" sound than the French pronunciation "akadjɛ̃", eventually got abbreviated and 'softened' to 'cajun'.

Languages are fun!