Hi Alex. I have had the same issue with my 70131 and have used 2216 from 3M. This is a slightly flexible high quality “space qualified” bonding material that bonds well to metals. I don’t remember what the max temperature is for this material but we used to cure it in a (vacuum) oven around 80-90*C.
After I have machined away the bonding material to close to the magnets I will wrap a high strength thread around the magnets and reapply 2216. This to let the embedded thread take the strain rather then the bonding material.
Hope it works out well for you.
Spannerman