Sounds like you care good about them. I hope they will do it.
Its a realy nice species, very active and agressiv (when colony is bigger) no hibernation and nice soldiers... But not as easy to keep as Lasius niger for example.
I think in a month there is a lot of brood and most workers are dead. The transport is stressing for the workers and reduces their life-span (normal 3 months for workers)
If the queen is healthy the colony will recreate in maybe 2 months. Be patient, later they will grow very very fast.
4 dead workers is still ok. dont worry about, but keep counting.
I never gave bean weevils to my pheidiole. Do they like them? Flys they like for shure.
I have one further tip for you. Make a ground of gypsum (CaSO4) in your arena. They like walking on gypsum more than walking on plasic. And you can keep the gypsum ground moist. Gypsum aspirates a lot of water if you cast it on. A moist ground is profitable for P. pallidula. At my colony moist ground has reduced the mortality

. The gypsum should be 1-3cm (0,5-1,5 inch) thick.
If you use gypsum be carefulm that no shugarwater etc. is aspiratet by the gypsum. it would be possibility of mildew.
Greetings