Biden definitely tried to solve the problem. However, immigration was being drummed up as a big issue and it was one of the few issues attracting people to vote Republican, mainly due to fearmongering.
And an oversimplified account of immigration was used to paint a “bOtH sIdEs” argument to get people who would vote Democrat to not vote.
Why would dollars beat votes?
Dollars are used to fund programs to get people to vote for your candidate and not the other.