They were involved, an audio had been leaked where Imran khan praised the attack.
In the alleged tape, he was woken up and informed about the incident and he made the said comment. From that conversation it was obvious he had no prior knowledge of the incidence or any involvement what soever. Further, just afterwards he and others clarified that they were not involved.
Noon machine had used the incident for their own propaganda, especially in the foreign press. Allegedly, Marvi and others were involved in orders to interrupt the transmission and damaging cameras. However sorting the facts is between PMLN and PAT workers (who were really angry after MT Incident.)
Anyway besides IK said good about the attack or not,
no PTI leader or worker had attacked on PTV or planned. That's the simple and straight truth.
But as I commented - in hot political vendetta, the facts rarely matter.
Rather PTI had made a point that its movement would be peaceful but persistent. That was the key point of its political struggle. Though PMLN kept on attacking PTI rallies for provoking violence right from the start. You. being a worker of Rizvi sahib, better understand and appreciate how PTI conducted that long sit-in and learn how Rizvi sahib failed to keep political momentum.