To answer your question, DisplacedCatsFan, if it were a Safety Touch, the Cats would have their choice of 3 options -- 1) take possession at their own 35 yd. line. 2) Kick Off from their own 35 yd. line. 3) Have Montreal Kick Off from their 25 yd. line. A team, which scores a Safety Touch will almost always choose option #3.
The answers to understanding the ruling on the Kick Off in question lie in the definitions of "Possession" and "Safety Touch," copied here from the CFL Rule Book:
SECTION 3 – POSSESSION
Possession means having the ball firmly held in hand or hands, arm or arms, leg or
legs, or under the body.
When players of the opposite teams have possession of the ball, it shall belong to the
player who first gained possession and who has not lost possession.
If players of both teams legally gain possession of the ball simultaneously, it shall
belong to the team that last previously had possession.
A ball not in possession of a player is still in play. A ball shall be considered to have
been fumbled if the player last in possession has lost control of it.
If a kicked ball other than a kickoff is legally touched by a player of either team, such
touching shall be deemed to be possession.
Article 3 – Safety Touch
A safety touch is scored when the ball becomes dead in the possession of a team
in its own Goal Area, or touches or crosses the Dead Line or a Sideline in Goal as a
result of the ball having been carried, kicked, fumbled or otherwise directed from the
Field of Play into the Goal Area by the team scored against, or as a direct result of a
kick from scrimmage having been blocked in the Field of Play or Goal Area.
CFL Official Playing Rules 2011
After a safety touch, the options to the scoring team are to:
(a) Scrimmage at their own 35-yard line,
(b) kickoff from their own 35-yard line or,
(c) Accept a kickoff from the 25-yard line of the team who conceded the safety