A common term for people who **do** work well with others is [*team-player*](http://dictionary.cambridge.org/dictionary/english/team-player). So you could say:

> Several co-workers who are not team-players caused the project to be delivered late.

If you want a term that is less perjorative, then [*uncooperative*](http://dictionary.cambridge.org/dictionary/english/uncooperative) is, perhaps, the most straightforward word to use:

> Several uncooperative co-workers caused the project to be delivered late.

Another possibility is [*individualistic*](https://www.merriam-webster.com/dictionary/individualist):

> Several individualistic co-workers caused the project to be delivered late.


If you want a term that describes the group as a whole, then [*incohesiveness*](https://www.merriam-webster.com/dictionary/incohesive) is possible:

> Due to incohesiveness, the team delivered the project late.

Alternatively, you could put it the other way round, and use [*cohesion*](https://www.merriam-webster.com/dictionary/cohesion):

> Due to lack of cohesion, the team delivered the project late

Finally, you could use *uncollaborative*, although this does not appear to be a dictionary word. The meaning, however, seems to be reasonably clear. See: [*Is “uncollaborative” a word?*](https://english.stackexchange.com/questions/53533/is-uncollaborative-a-word).

> Several uncollaborative co-workers caused the project to be delivered late.