Swanstone wall seam failing

[MrsZ]

We have a 3 piece swanstone shower surround there are two 'L" shapes at the front and back then a side panel that overlaps the L pieces. The overlap closes to the shower is pulling apart. It's secure at top and bottom but the middle is pulling open and I can see the pressure tape that was used in installation. Can this be repaired? My initial thought was to clean out any adhesive, apply silicone, brace it for 24 hours and hope for the best then caulk the seam. But seeing that pressure tape has me uncertain on what to try. Thanks

 

[WorthFlorida]

Your walls or floor are not stable enough and the corners may not be square. As the house walls move from season to season the shower surround is attached to it so it moves the surround panels with it. The panels are glued to the walls so any movement, the panel moves. Movement, I mean maybe only an 1/8 of an inch plus the extra moisture from the summer weather and shower use. Really can't say what the best fix would be.

https://abgprdcdn-swan.azureedge.ne...tion-guide-1960719.pdf?v=1&d=20190917T174217Z