The problem is that while al jazeera can be balanced about certain topics, fact is it is entirely government funded by an authoritarian undemocratic state and on this topic in particular it seeks to purposefully take a prejudiced anti Israeli stance. It has also been criticised for biased to the Syrian dictator, and takes various stances according to the foreign ministry. We therefore cannot be certain if the claims are true.
Unfortunately as history has repeatedly proven, propaganda works. At the very least maybe source should include Government funded?
You can make a similar case against any media organization. They all publish true things and false things. They all have biases that highlight certain things that are happening while occluding others.