If you want to find all the loads which apply, you will need to do a force vector diagram. They are not that difficult once you read about them. The force to begin with is the load which will be applied by your motor and screw, taken from the torque curve diagram. Start off by assuming the router is off, the screw has full load and the system has stalled, this is a static state. Then apply the vector diagram to a moment diagram where all the moments are equal to zero. although this is unlikely it is a start, it would be the maximum in the event of an error. In the catalog, there are formulas to determine the load you are going to have (max load) which will be known frm your moment and force diagrams. That will tell you if it is ok or not. the other thing is that there are two brg blocks which would counter act each other for moment. Also, I believe the bearings you are using have a reduced maximum load if mounted on their side.
OR... seeing you are near finished just do it. If the system bends and stalls, you will need to add the other bearings. If things work your off to completion. Its all in the fun of DIY.