Jointly founded centre to host hundred on uncertain date (2-7)

'jointly founded' is the definition.
I can't judge whether this defines the answer.

'centre to host hundred on uncertain date' is the wordplay.
'centre' becomes 'core' (core can mean something's centre).
'to host' is an insertion indicator (inserted letters are hosted or welcomed).
'hundred' becomes 'c' (Roman numeral).
'on' means one lot of letters goes inside another.
'uncertain' indicates anagramming the letters.
'core' going around 'c' is 'cocre'.
'date' with letters rearranged gives 'ated'.
'cocre' inserted within 'ated' is 'CO-CREATED'.

Can you help me to learn more?