The popular utility player was stretchered off the ice in the final minutes of the contest falling a fall.
This means Bison boss Doug Sheppard will have to re-shuffle his forward lines for the final league game tonight and then a play-off quarter-final clash with Sheffield Steeldogs next weekend.
The opening period saw two home town boys scored for Swindon, as first Lee Richardson netted from Henri Sandvik and then Aaron Nell, a hat-trick hero when the Herd were last in Swindon, scored their second.
The second session saw the Bison increase the pressure on their former goalie Stevie Lyle, but they could not find a way past him.
It was Swindon’s all Brit line that added to their tally as Ryan Watt netted from close range at 26:43.
A couple of early Bison powerplays early in the third period gave the visitors hope, but they were unable to break their duck.
The Herd then lost Ciaran Long at 49:52, as he sat out the rest of the game in the sin bin after he picked up a 2+2+10 penalty for attempted butt ending.
At 53:57, with the powerplays over, Lyle skated off to be replaced by Martin Crisp.
Soon after team captain’s Shane Moore and the Herd’s Nicky Chinn both picked 10 minute misconduct penalties.
The Bison finally got on the scoreboard at 59:36 as Stuart Mogg from close range, this was just after Wales has been stretchered off the ice.
The Bison wrap up their league campaign with a visit from the Milton Keynes Lightning tonight and will then focus on play-off glory next weekend.