So I think I understand what you're looking for, see if this helps.
All I did was create conditional formatting for column C. If you select on cell C2 and then click Conditional Formatting>Manage Rules, you can get a look at the formula I used.
The two formula's I use for the conditional formatting are: =AND(C2>D2,F2="Follow Up") & =AND(C2>D2,F2="Wait")
If the first is true (Days Since is greater than Days Allowed & Column F="Follow Up"), the cell is filled with red.
If the second is true (Days Since is greater than Days Allowed & Column F="Wait"), the cell is filled with gold.
If neither are true, the cell remains with no fill.
I also converted row F cells into list validation which only gives the user the option to select Wait or Follow Up. This will prevent you from accidentally typoing in that column and potentially causing the conditional formatting from malfunctioning.
The validation list is found in cells K1 & K2. If you want you can either move that list to another worksheet or just hide the columns so you don't have random data just floating around in view on your primary worksheet.
Let me know if this helps.
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