I dont have any lists with 2 units but theory crafting a bit I'm sure there are competitive uses for them. For everyone they are pretty good jammers and the bokor can put out decent damage with death magic, especially if being fed corpses from croc pots and other units.
For Barny 2 and jagajaga they are utterly disposable feat targets, and barny 2 in particular likes a big screen/jammers so that he can stay unjammed himself.
Under Rask they can actually do a respectable amount of damage for their cost. Although Rask super friends is his most popular list I think people really underestimate how strong Rask infantry lists can be.
Calaban can help fix their accuracy and damage with carnivore and parasite respectively. Barny 1 also helps accuracy with death March and his feat. However I dont think there is as much synergy with these 2 as there is with the other 3 mentioned.
In any case to run them effectively you'll need at least 1 croc pot but probably 2 to run them. This probably wont be a problem though if you are also running boneswarms.