I don't think it's a problem to feed T's whatever gogos. Silkworms would have a lot of protein, but beware. Some time ago a chemical was used in the North east, that prohibited the metamorphic stage of worms, that wiped out the whole silkworm population in the Tzaneen area. The silkworms would grow nice and fat and appeared healthy, but as soon as they changed into pupae, they all died. This would have a devastating effect on a T in molt stage.
I don't want to start a scare about it and it's not a rumor. My own kids silkworms all died back then and that was the reason for it. Our neighbor was the main supplier of that chemical, supplied to the citrus farmers in the Letsitele valley. Other than that, silkworms would not be natural prey. So, if your source is trustworthy, use it or not, but luckily they only have a short season.
Roaches, like Dubia's etc, are a natural prey from South America. They contain more protein than crickets and don't stink or jump. Yes they gross me out as well, but they're good feeders.
Africa is a tough country. When the going gets tough, we get going.