Can't create a bootable CentOS USB?

I have no issues creating bootable USBs from downloaded ISOs for other distros. I'm using 'startup disk creator' in Ubuntu, and it doesn't seem to work, for whatever reason. I see an 'installing' popup that does nothing, and just sits there until I close it.

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I have tried both the minimal ISO, and the DVD ISO, with no success.

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Any suggestions? Host machine running Ubuntu 19.04.