What legal training do you have to know what are, and what are not, grounds to rescind a contract ?
Even if you were qualified to make an assessment as to whether Rontan does or does not have grounds to back out of the deal, you would still have to know what the actual basis is for Rontan to have backed out of the deal.
With that said, please let us know what specifically are the bases which Rontan has provided to GDSI relative to its decision to back out of the deal.