Hi there honey, first things first, if your LO is suffering with teething or a cold there is sadly not much you can achieve by tweaking the routine to make things better, it may just pass a the cold & teething do. Are you medicating to ease any teething discomfort?
As you begin the 2-1 you'll need to decide whether you're going to keep a short first nap and long second or vice versa. From your notes it seems you were capping the first nap. If you're going to do that, you don't really want to make it a full A time prior to the nap. Ideally, he'll be going down for the nap a little UT and then should be sufficiently restored by the CN to make it through to the afternoon longer nap. So maybe try sticking to 10am but waking him up after 45mins?
If this works, I would then work on extending that second A time to get a good long nap in the afternoon and then hopefully keep a good night. You might find the day needs to lengthen for a while as this process settles.
Hope that helps x