Our sysadmin team needs us to exclude anything 10.64 because out pxe server is responding to requests faster than their pxe server. How can I tell our SCCM server to not respond to anything 10.64?

There is no way to do that, however, you can set a delay on the PXE response. In the settings of the PXE server through SCCM, just increase the delay incrementally and that should fix your issue.Scott Gill SCCM Consultant

We did that and wasn't sure if that was the only way. Will our computers respond to their PXE server?

That depends entirely on how your network infrastructure is setup. You should be working with the network team to see if you can create "boundaries" on the network by blocking bootp packets in certain area's to avoid this issue.Scott Gill SCCM Consultant