Help! Need help resecuring slide column!

[Freech]

Any suggestions on where to place new screws so the slide doesn't come away from the trailer? We have tried using longer and fatter screws (as well as more screws) but it is still coming apart. Winnebago says "You could utilize the Z-mounting bracket to resecure and provide additional support" but has not provided any more detail other than "Lippert sells the brackets directly from them". Lippert says he doesn’t know how the OEM installed our slide so he was limited on how he could help other than providing information on the slide itself. Is there a source that will show us how the slide was installed so we can see where to place the screws that will secure the slide column? Thanks!!