The former Nottingham Forest midfielder has been on trial with the Glovers but having not featured in the 4-1 defeat to Cardiff on Sunday his time at Huish Park looked to be over.
But Johnson has revealed Gillett, released by Forest in May, is weighing up his options.
"We had a chat with him and we had a chat with his representative about what might be available and what isn't," he told the Western Gazette.
"Some of these players have been used to pretty high wages in their time. I think he is looking at other options at this moment in time.
"Myself, I think he will have made his decision by now. At the end of the day, I'm comfortable with that so it's not a problem."
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