Regarding the vfio-pci advice: consider to post dmesg outputs that concern vfio, as explained in the original answer, and also consider posting verbose output from EAL initialisation. Without such information, it is very hard to guess about what might have gone wrong with the particular setup.

In what comes to build errors (which, by the way, make another question unrelated to the topic of the OP), it is hard to advise on third-party instructions that are not part of the upstream DPDK project: if those tutorials worked previously, consider reproducing them step-by-step, exactly as when they worked. Yes, vendor-specific tarballs may differ significantly from the upstream DPDK contents. So one shall make sure that all versions and sources from which the code comes, as well as command sequences used, follow those outlined in the tutorial.