Yeah, “adjunct” research positions are not the right ones to look at. He’d want to look at research assistant positions, which are the ones for undergrads and recent grads. You don’t say what discipline he’s in, and that’s important: natural/life sciences labs and medical research labs are the most likely ones to have paid positions for research assistants still open right now in the pandemic. In psychology, many labs at research universities have 1-2 paid positions for research/lab managers.
Depending on the field, there may also be opportunities outside of academia - like at nonprofits and think tanks or whatnot.