Club captain Rollins and fellow attacker Thewlis both served three-match suspensions for their part in the brawl as the Pilgrims beat Leamington.
Their time on the sidelines coincided with striker Jake Wright suffering a torn hamstring, but they are eligible for selection again following Saturday’s contest at Hereford.
“We’ve missed our three strikers,” Elliott said.
“It’s been hard and I knew when they got sent off that night we’d miss them.
“They’re not only good players in our team but some of the best players in this league, so of course we’ve missed them.”
United retrun to action tonight at Kettering Town (KO 7.45pm), looking for their first away win of the season.