Of course he has a chance. There's nobody Dustin doesn't have a chance against.
Islam's striking is good, but ironically that could get him into trouble. It happens a lot when guys are really good everywhere, and will go at their opponent's strength just to prove a point. Even if Islam did go straight to grappling, Dustin is a black belt and he's only been subbed by Khabib and Charles, then his other sub loss was like 12 years ago. Charles got the crap beat out him, couldn't take him down in 6 tries, and got kind of lucky in a scramble on a failed TD to end up in top position, and eventually got a standing sub after multiple failed sub attempts. It's not like Dustin is some white belt you can just grab and sub, and he's still possibly the best striker at LW.