Inflatable pillow pinhole leaks...how to cheaply fix

I’ve got a lightweight inflatable camping pillow, an trekology aluft 1.0. Its done very well and I like it very much. However, it has sprung multiple pinhole leaks on one side of it. This makes me suspect that the fabric has aged and failed rather than a single externally cause puncture. I would like to coat the inside of the fabric with something to plug the holes and perhaps prevent others. I know of the “tire in a can” products and the bike tire ‘slime’, but I don’t know if those would be suitable.

I’m looking for suggestions (cheap?..the pillow costs $16…I don’t want to spend $10 fixing it) on what to coat the inside with. Does the slime ever dry or does it remain goopy?

Any thoughts on this? I’ve bought a replacement, so this is essentially an experiment waiting to be carried out.

I used to fix holes in an air bed with a mixture of baking soda and super glue.