The right-back has not played since the 4-0 victory over Dagenham on March 6 because of an ankle injury, and Caddis is expected to miss both of the Robins' games over the Easter weekend.
Wingers Matt Ritchie and Lee Holmes were rested for the 2-0 midweek success at Barnet but both come back into the reckoning at the Globe Arena, while striker Paul Benson should shrug off the after-effects of a neck problem to feature up front.
Simon Ferry is set to return into the middle of midfield, while Alan Connell is pushing for a recall alongside Benson.
On-loan forward Jonathan Tehoue has been told by manager Paolo Di Canio that he has no future at the club and will therefore not be part of the matchday squad.
Morecambe boss Jim Bentley has no new injury worries.
On-loan Carlisle forward Craig Curran is in line to make his full home debut for the Shrimps, with Bentley strongly tempted to stick with the line-up triumphed at Oxford last weekend.
Curran opened the scoring against the U's before Stewart Drummond sealed victory with his fifth goal of the season.
Shortly after Drummond's winner, Kevin Ellison was withdrawn. However, Morecambe's top scorer in understood to have not suffered any setback with regards to his long-standing back complaint.
Midfielder Andy Fleming and defender Laurence Wilson are both out for the remainder of the season with knee injuries.