Maybe if you were to get a SIM card from a provider which allows you to check your texts online and then share that login info with your presenters. Not sure which providers offer this though. I know o2 allows you to send but not sure about receive.
We use iTagg. We have the keyword TD1 which users must start their texts with. They send this along with their message to 60300. The iTagg system then processes the text and sends it as an email which comes into the studio computer. The cost for this is about £60 per year...