Are you seriously suggesting that Gaza is the only problem the Democrats have?
This is what you do, when you want to take votes from the Democrats. If you wanted to built up real power, to challenge the Democrats from the left, you have to win local smaller elections first. That means city council, house of representatives, state level politicians, school boards and so forth. You focus on the most left leaning regions, so you can actually go first past the post. The Greens do not do that. They run in FOUR elections in California this year. That is the largest blue state, with some very left leaning areas.
Also once you sit in congress, councils or whatever, you need allies, unless they win a majority. So in most cases that would mean winning the furthest left seats and having to work with a more centrist party, to change things. In the US that would be the Democrats. In some countries there are deals made to not run candidates in certain districts, to make sure left parties win. That just happened in France for example. No reason those deals could not be made between the Democrats and the Greens.
Also Gaza can only be solved by becoming president. Jill Stein is not going to win the election and everybody with half a brain should no that. So the goal of running, should be to show what the Green Party stands for in local elections. Nobody can solve Gaza when sitting on a city council in the US, however they can built bikelanes, promote renewables, improve public transit, cheap dense green housing and so forth. Jill Stein does not mention those at all. She should, to help out the local candidates, which they are not running. It also means less issues the Democrats might copy. After all who cares, if the Greens or the Democrats pass good laws, as long as they are passed.
Attacking the Democrats from the left is just going to hurt the Democrats, which helps the Republicans. Instead the Green Party should either try to built an alternative or push them towards the left. Right now it is obvious that they just want to help the Republicans.