I have sandy soil in the front of the house so I get 'em quite regularly . A green block or poison peanuts usually take care of them .

The bed in question has landscape fabric so I'm guessing that's what kept me from seeing any mounds .

I lost a cherry tomato there . Planted one day and was gone by morning . Pretty sure it was gophers as I had the cage wrapped and there was no sign of rabbits digging under the plastic . Also had a couple of roses die from their roots being chewed off .

Question is : Is it safe to use the afore-mentioned poisons near any vegetables ?

I would not use it unless it says it is approved for gardens. Look at GopherHawk traps. No digging and you can keep setting it in the same place. I have caught over 75 in the past 3 years with them in our neighborhood.

https://www.lowes.com/pd/AMDRO-Gasser-6-Count-Gopher-Killer/3651779

i used this in my backyard where you could find the gopher mound holes...worked like a charm

I checked out the GopherHawk today . Seems like a good trap . I've also used the "gassers" but the problem is there are no mounds in this particular area .
Made a few hardware cloth cages to plant things in until I can figure this out .

The GH comes with a tapered probe to open up the ground to insert the trap. There is a probe that is attached to the top cap that is about 1/4" in diameter and pointed. Use the probe to locate the tunnel running thru the garden area. I would check all around the cherry tomato you lost.