OK I was just thinking this through during my run and I think I finally have a handle on Lalo's evolving plans over the course of the season. Tell me if you think this all checks out, or if I'm missing any details that might undercut my theory:
After Lalo escaped the assassination attempt, he came up with Plan A, which was to fake his own death, go to Germany to get proof of the Superlab, then sneak back to NM and take actual video of the site, which he would bring to Don Eladio, all without Gus knowing.
That's why he reacted so angrily when he realized Hector's phone was tapped; up until that moment, he believed that the only person who knew he was still alive was a trusted relative who was physically incapable of telling anyone else; he didn't know Gus had deduced it from Hector's expression. (Ironic that both Lalo and Gus are ultimately done in by the same mistake of unnecessarily speaking to Hector.)
At that moment, Lalo went to Plan B, which was to manipulate Gus and Mike into shifting their security around so that they were concentrated in areas that he didn't care about. So first he makes them think he'll be making a frontal assault on Gus' safe house, then that he's at Jimmy and Kim's. He wants them running all over town chasing their tail while he takes advantage of their confusion to proceed with his plan to infiltrate the lightly secured lab and make the video. (Unclear if he thought he would need to kill the security guards there, which would obviously have alerted Gus; I suspect his goal was to do it without anyone realizing he was there.)
However, this plan was foiled by Gus showing up at the lab. I said earlier that I wasn't sure either man expected to encounter the other, but I'm now wondering if Gus knew exactly what he was doing. He knew from the moment he was reminded of "spice curls" that Lalo would be trying to expose the lab, which was why he hid the gun there. When Kim said that Lalo didn't care which one of them went to Gus' house, he realized Lalo was toying with them. So maybe he figured, rather than let Lalo lead Mike on a wild goose chase, he would go there and end it once and for all. (Only problem with this theory is why he wouldn't have told Mike what he was doing; maybe he didn't totally trust him, or maybe he knew too much security would scare Lalo away. Or maybe he just knew it was ultimately going to come down to the two of them going mano e mano.)
At the moment Gus showed up, Lalo was forced to move to Plan C: take out Gus' security detail, make the video with him in it, shoot him, and then bring the video back to Don Eladio. He was definitely going to kill Gus; no way he could have assumed he could smuggle him back to Mexico without getting caught, especially with Mike and his team just minutes away.
And he would likely have gotten away with it, if he hadn't make the fatal mistake of underestimating Gus as a "house cat" incapable of besting him in physical combat