Truth is--he knew what was going to happen, so this looks just like another excuse to rant.
If I recall correctly, the pangu dev team attended some of his sessions about iOS hacking and used this knowledge to create a publicly available jailbreak tool. He then started to rant about how they "stole" his technologies on twitter (see for example https://twitter.com/i0n1c/status/481020166483238912).
More about his childish public behavior related to the jailbreak scene can be read here: http://www.iclarified.com/41983/pangu-jailbreak-stops-using-...
After the first release, pangu replaced his bug by one of theirs (and both bugs were fixed by apple in a subsequent iOS release.) He probably had to spend some time finding a new bug to use in his classes so it's understandable to be pissed.
A sibling post said they took his code. That's a fair complaint, was it clear when they saw it that it was not code that they could reuse?