Visa cancellation in oman

Hi good day ! I have few questions, currently my two kids and my mom is here with me in Oman, they supposed to leave Oman last year but due to some circumstances they stayed, to cut the story short they overstayed. My previous employer didn't help me to extend their visa due to some conflict between us, now they told me that they have to cancel the visa because they need to take another visa for new employees and in the police station they are not able to give them because of the expired visa of my family. Now I'm in the middle of confusion, because we are planning to leave Oman but I'm still saving money for the fine that I need to pay in the immigration, my question is

1. How much per day is the fine for overstaying?

2. If my employer will cancel my family's visa, can they transferred to another sponsorship like my husband's boss?

Thanks