Venezuelans who come to the US tend to be wealthier, in order to be able to get here, and have enough issues with their country in order to leave, issues that they will usually blame on the leadership.
None of this is to say Maduro has majority support, he doesn’t by most accounts, or that they don’t represent a sizable chunk of Venezuelans who don’t like Maduro, but that his support isn’t as non-existent over there as it is here.
It’d be like if Trump took over the US and you only got your views on what Americans think from expat communities in Canada. They would probably cheer his death, even if it was by a foreign empire, but that wouldn’t be representative of average Americans who probably wouldn’t like the foreign intervention, even if they don’t like Trump.
I realized this when I first visited Mexico, what you see here is not necessarily representative of that nation. The people who come here are the hungry ones looking to make money or just get out of Mexico. When I went to Mexico City I suddenly saw lots of BMWs, Mercedes, nice homes (and a lot of rough areas), etc. The people who come here come here because they are poor and ambitious/desperate, the well to do ones stay there.
A similar thing with Indian immigrants but we get the ones with higher education, the money to leave and live here, fluent in English, curious and ambitious, etc. The poor and uneducated aren’t coming over.