Re: wrong IP address allocation
Yes, that's good approach.
Check and compare affected workstations' ipconfig with nslookup <workstattion-name> run on workstation .. those are supposed to be same.
If it's FSSO setup then check nslookup on DC where Collector runs. As THIS is the point where DNS lookup or getHostByName is done and from this point of view is the IP resolved. And again, if whole DNS works well then even this nslookup result should show same IP as on workstation. You might also want to check that DC and workstation has same DNS setting.