I know this stuff can work to some degree, temporarily at least. I think you will find the guys doing the tyre change will stop as soon as they realise whats in the tyre, because its horrible stuff to work with when changing tyres. you might be wise to ask first, or simply take the tyre off beforehand, when you come to the replacement of the tyre. Alternatives are on the market such as the rubber bungs that are used simlar to a proper repair but from the outside, they come with a small cylinder to replace the air lost in puncture and they are rather good once mastered. There are also some plastic screws you can buy now (they look a little like plaster board scews) but I wo'nt comment on these ,as I have not used them.
There is no better than a tyre without a hole, repaired or not! says a man who out of need, has stuffed tyre with hay! to keep moving.
Be wise, be safe,