A common term for people who do work well with others is 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 is, perhaps, the most straightforward word to use:

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

Another possibility is individualistic:

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 is possible:

Due to incohesiveness, the team delivered the project late.

Alternatively, you could put it the other way round, and use 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?.

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

A common term for people who do work well with others is 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 is, perhaps, the most straightforward word to use:

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

Another possibility is individualistic:

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 is possible:

Due to incohesiveness, the team delivered the project late.

Alternatively, you could put it the other way round, and use 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?.

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

A common term for people who do work well with others is 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 is, perhaps, the most straightforward word to use:

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

Another possibility is individualistic:

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 is possible:

Due to incohesiveness, the team delivered the project late.

Alternatively, you could put it the other way round, and use cohesion:

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

A common term for people who do work well with others is 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 is, perhaps, the most straightforward word to use:

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

Another possibility is individualistic:

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 is possible:

Due to incohesiveness, the team delivered the project late.

Alternatively, you could put it the other way round, and use 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?.

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