I searched to some extent in regard to the importance of 22nd Rajab according to Shia view. I solely found a matter regarding this matter. Seemingly, at the above-mentioned day, Imam Jafar al Sadiq (peace be upon him) has done a miracle. It has mentioned it as Konday and likewise the miracle of Imam Sadiq (peace be upon him). (But to be honest, it was in Pakistani language, thus I was not able to figure out what it say). For further information, you'd better to the reference below if you are familiar with Pakistani.