Should I also screw the ridge that has butyl tape, even though all other screws are in valleys?

Hi, your forum is great, many thanks! I'm installing a corrugated roof on a monoslope shed (low pitch of 1:12). It's standard 2 1/2" corrugated, 29 ga., overlapped 2 ridges. Manufacturer says to screw in valleys, and to put a strip of butyl on the outermost ridge, which I did. I'm using 1/4" x 3/16" butyl tape, and I screw the valley right next to the tape. But the butyl tape lifts the edge a bit, so the edge seems a bit high to me. And when I look under the edge, although the butyl has sealed about 95% of it, I can see several small areas where the butyl hasn't sealed, so there's a small "hole" or gap.

I tried gently but firmly pressing down on a hot day, and that helps a bit, but not completely. Rain doesn't seem to be a problem, given that there's another ridge the water would have to climb before reaching the underlying panel's edge.

I live in the Northeast so I'm wondering if ice buildup will lift the edges?

If so, what's the best solution for this... should I screw through the ridges where the butyl is? Or just apply tube sealant to the edges? Or something else?

Many thanks!