if you don't think the quality of the trial is so bad as to outright impair approval (and right now the political pressure for a tool, any tool, to fight COVID is so intense that there's zero chance it wouldn't be) then why continue? It costs money to do trials and it represents lost revenue where you could be the sole seller of the only known drug to treat a deadly pandemic.

in fact there is a downside risk to continuing as well, further study might show that the early results were an outlier and the drug is not as effective as previously thought (or has some serious side effects in some situation), and then you lose all the money you've invested. But if you push it through, there is no risk of being sued since the US Government has waived any liability on the part of drug companies for these therapies.

in a game-theoretic sense there is absolutely no benefit to continuing the trials and potential downsides to doing so. Remember, for-profit companies don't care about maximizing public health, they care about maximizing revenue. Especially when you've explicitly removed all financial liability for being risky with public health.