So My question is. Is my credit score going to be hit?
Yes it will affect your credit. Not as much as missing payments on the debt, which remains even if the credit line is closed, and not as much as missing payments on other bills...
If so what can I do about it?
Not very much. Nothing worth the time it would take. Like you mentioned, reopening the account or opening another would likely require a credit check and the inquiry will add another negative factor.
In this situation, consider the impact on your credit as fact and the best way to correct it is to move forward and pay all your bills on time. This is the number one key to improving credit score.
So, right now, the key task is finding a new job. This will enable you to make all payments on time. If you pay on time and do not overspend, your credit score will be fine.
Can I contact the creditors to appeal the decision and get them to not affect my score at the very least? I know they won't restore the account without another credit check). Is there anything that can be done directly with the credit score companies?
Depending on how they characterize the closing of the account, it may be mostly a neutral event that has a negative impact than a negative event. By negative events, I'm referring to bankruptcy, charge offs, and collections. So the best way to recover is to keep credit utilization below 30% and pay all your bills and debt payments on time.
(You seem to be asking how to replace this line of credit to help you through your unemployment.)
As for the missing credit line and your current finances, you have to find a way forward. Opening new credit account while you're not employed is going to be very difficult, if not impossible. You might find yourself in a situation where you need to take whatever part time gig you can find in order to make ends meet until your job search is complete. Grocery store, fast food, wait staff, delivery driver, etc.
And once you get past this period of unemployment, you'll need to catch up on all bills, then you'll want to build your emergency fund. You don't mention one, but eating, paying rent/mortgage, keeping current on bills, and paying debt payments are the reasons behind the emergency fund, and the reason you need it in a liquid account.
Source: I'm a veteran of decades of bad choices when it comes to money, of being unemployed for periods of time, of overusing credit cards, and generally being irresponsible with my income and savings. I've done all those things and am now paying the price. In order to rebuild my credit, and provide for my retirement, I'm having to work very hard to save. My focus being financial health, not credit score, I've brought my bottom line from approximately 25k in the red up to about 5k in the red. The first step was getting my payments under control.
I have also been watching my credit score. Two years of on time mortgage payments, gradual growth of score. Paid off student loans, uptick in score. Opened new credit card with 0% intro rate to consolidate a couple of store line of credit accounts. Transferred those balances. Big uptick. Next month when utilization on that card hits 90%, downtick that took back a year's worth of gains. However, financially, I'm not losing 50-100 a month to interest.
TLDR; At certain times, you have to ignore the credit score and focus on the important things. This is one of those times for you. Find a job. Get back on your feet. Then look into living debt free, or working to achieve financial independence.