The kits being used, when last I read about it, are of two types. Those being tested because they have symptoms are with an approved kit. Those being tested who are healthy and just wish to be tested are using a kit that is not approved. This does not mean one is "better" than the other, simply that the approved kit has met FDA standards as being valid enough for use. The non-approved may be less accurate, equally, or better but it has not been vetted. The FDA, not the CDC, approves kits. They have relaxed their usual lengthy evaluation under an emergency authorization to allow more manufacturers and labs to get their kits into use.
Thus there are kits that are FDA approved that down the road may have been less than the quality we would want in a perfect world. You can read about the process for FDA emergency authorization
HERE
The OP is expressing concern that UF was using defective CDC kits at the polo field. This is mixing up two events. At the beginning of the COVID outbreak there was no test for the virus as it was new. The Chinese gov't within a couple weeks of the recognition that this was a novel disease had the genome of the virus sequenced and found it did not match any known pathogen. The Chinese made the genome information public on Jan 12th. They then began producing a kit to identify the virus which was simpler than doing a genome test on every sample. As the possibility that this would not remain localized was recognized, other countries began developing their own tests, including the US where it was being done at the CDC.
Some countries were successful at rapidly producing and deploying kits. An excellent example is South Korea. However, sadly, the
kits that the CDC made and on Feb 7th shipped out to state health departments were failures. This was realized when the end users ran controls on the kits. A control is a known sample. If the kit is working the known positive control should always show as positive when tested, similarly for negative control which should always show as negative. These defective kits were NEVER used on patients but it took some time before the production failure was recognized. It is not clear why the control failure was not noted before shipment.
With the CDC being the facility that was making kits now having failed, the FDA issued an
emergency use authorization EUA on March 16th allowing others to use kits they had produced that had not gone thru the FDA approval process. This has taken up many weeks and we still do not have enough kits for the testing demand. Identification of genome Jan 12, CDC kit failure noted Feb 7, FDA authorization for other kits Mar 16th. It should be noted that in the run up to Mar 16 private and university labs were working on making COVID kits but until the FDA EUA they could not use them except as part of a study.