Friends Axys randomly dying

My friend has this problem on his brand new limited 2017, he has no time to go the dealer yet (longer trip) and I told him I will try to ask in the forum. The sled was ridden for 3 days, day 1 was without issues, day 2 it randomly died 2 times, day 3 it randomly died 5 times during the whole day, so the issue is clearly getting worse. It dies (cuts off) when at idle and also with some throttle, didn't happen so far when trying to switch to reverse. Could this be TPS? Could this be something with tether (There is oft racing polaris tether installed)? I never experienced anything like this with my old rmk or axys, any hints welcome, thank you

I edited this to add some new information I received from him. He is quite a sled newbie but he reported that after sled dies he needs to give full gas to be able to restart it. It will not restart the engine without giving throttle

yeah I thought about that also and I even recently read a thread on this forum about such an issue but still to me this seems very unlikely. Do you recommend to dismantle the whole throttle?