The 1" thick top presents a couple challenges:
- Stronger inserts like those shown are 1" deep and will pop through the top.
- minimal screw thread engagement holding a flexible table slide
Since you pictured an equalizer slide, assuming you have center mounted the slides to base plate between legs?
Making a more permanent slide attachment to table top, might require making the top/slides and center mounting plate removable as single assembly. Basically unbolting the slide mounting plate from legs to enable break down for transportation. I used a couple of square head bolts through each trestle leg top, with washers and nuts on top attaching a BB plywood plate, for clean look on bottom.
Along those lines, suggest an improved mounting to table:
Add a ~2×4 or 2×6 hardwood plank to table underside, on the outside of the anchored ends of table slides. The plank should be same width as height of slide. Glue and screw the plank to table bottom. Cross drill the table slide (missing the dovetail slot) and screw the slide horizontally into the anchored plank, as well using screws from bottom. The horizontal screws need to be countersunk to deal with slide opening/closing. This will dramatically improve the attachment strength to table top.