That reconstruction video highlights the massive problem that is lurking for the defence in the police interview IMO. The PCA alludes to this trainwreck.
Trail walking woman sees a guy resembling Bridge Guy on the bridge from 50 feet, before turning back, and seeing the victims. It will be established at trial, IMO, that she must have seen Bridge guy. Keep in mind each evidential fact does not have to be established beyond reasonable doubt. Remember that Trail woman does not encounter RA on the path, nor does RA report seeing her. This is crucial.
The victims now proceed down the 'flight path' to Bridge Guy. Realistically no one else can be between them, as Trail Woman sweeps the path.
At the same time, RA, rather foolishly, admits to seeing the 3 girls. This puts him on the 'flight path" to be at the bridge, dressed like bridge guy, at approximately the time Trail Woman will see Bridge Guy.
So here are the obvious problems.
1. If RA retraced his steps from the Bridge, how can RA get off the victims "flight path" without seeing them?
2. Where can RA have been if Trail Woman did not see him, but saw the 'real killer'
3. If Trail Woman somehow saw RA and mixed him up with the real killer, where did RA go, in order for Bridge Guy to get on to the Bridge, and the victims to advance down the trail, without RA seeing any of them?
This is where Law Enforcement have tripped him up IMO, most likely by selectively revealing the witnesses info to wreck his story, after he already admits he went on the trail and walked back (reading between the lines IMO).
The defence version will need to be item 3 - that Trail Woman saw RA on the bridge (where else could he be). This is the only way for her to see him, but him not to see her. He must be on the bridge. But now he has to get off it before the victims get there, so real Bridge Guy can get there, appearing from behind the victims direction of travel.
Therefore, the victims will meet him on the trail before when he retraces his steps ----> he must see the victims, unless he somehow went off the trail, or they did.
Admitting to seeing the 3 girls back in 2017 is fatal, because it puts him on the Bridge for Trail woman to see. But she also must have seen Bridge Guy - proving RA is Bridge Guy.
The only way out of this is fanciful stories about how the victims somehow didn't go directly to the bridge, allow RA a moment to slip past.
But my guess is RA has flubbed the interview when confronted with these problems. They will have encouraged him to commit to a version, before selectively revealing their cards, and inviting him to elaborate.
In the PCA, they just say there is no way for him to get out other than as muddy/bloody guy - but the evidential problem is going to be how he evolved his story of getting out.