T1 entrepreneur Visa £50k refused need advice

Dear All,
I am Muhammad has applied T1 entrepreneur Visa got refused on 12th March 2019.
I applied for AR on 3rd April which is been refused on 29th April. Reasons below,
Credibility of business not satisfied
Credibility of accounts not satisfied
Credibility of business activity not satisfied
Job creation not satisfied because only 1 employee got paid in cash.
All the RTI of all employees been provided but not satisfied.

My 10 years period would complete on 20th of September 2019 after deducting 28 days.
I am going to apply for T1 entrepreneur fresh application within 14 days now.

I need honest advice from anyone who can answer the following questions.

1. Shell I go for fresh T1 entrepreneur application first to keep my 3C continued and then after go for JR against AR refusal as well ?? Just want to keep both ways in my hands to complete remaining 4 months.
I am confused here, can I choose both ways or not?
2. If I choose both ways still my 3C would be considered or not ??

I have applied my whole family visa with 2 kids. They both kids born in the UK. My older Son is just 5 years now have got Cochlear implants in both ears and getting treatment in the UK.
My wife gone back to home country for her mother death with one child but my older child who is getting treatment here is with me in the UK. My question here is

3. Shell I apply for myself only or my older son's application as well. I do not want his application with me now because he born here and I will apply his passport after getting my indefinite Visa.
Would home office have concerns if I will not put his application with me or not ??
Many thanks

Your Section 3C protection ended when AR was refused.

JR is not a process under the immigration rules and does not extend Section 3C either.

It would be useful if you want advice, to post the wording of the refusal (taking out personal details).

You are currently an overstayer as is your son as your dependent. So there are a few points you should consider:

Your son is no longer entitled to free NHS treatment so bear that in mind when they start asking for you to pay for treatment going forward.
Your ties to this country are now questionable as half your family in now back home with no means of returning. So the argument for remaining here is weakened.
Applying for a fresh Tier 1 Ent - that route is now closed for new applications. So what exactly would you be applying for? Certainly not for Tier 1 Ent extension, that boat has sailed.

Whatever visa type you are going to apply for you have to include your child.