Hi there, (((hugs))) for all your NWs, that sounds so tiring.
First of all, PUPD is generally not recommended for a LO with reflux. It can aggravate the reflux and hinder the self-soothing process. So, in your quest to settle at nap time and for a NW, I'd use shh-pat or some variation (can be rubbing the back, stroking the forehead, singing or humming) to settle. Does he ever go to sleep independently or do you end up holding him to sleep each time?
Secondly, reflux can definitely flare up while a LO is teething. It definitely sounds like he might be In some pain at those NWs, since his eyes are closed, he's screaming, and then settles when you pick him up. Does he sleep on an incline to help with the reflux?
What types of things are you feeding him for solids? It could be that they are causing some tummy troubles, which are also hindering the NWs. I'm curious about the porridge before bed. Is there a reason for that? Typically, you wouldn't want to feed solid food so close to BT, as LO can still be working on digesting it when they go to sleep. And porridge is oats, right? Those aren't the easiest to digest to begin with.
It might be worth dropping that for a week or so to see if it helps.
As for your routine, it looks pretty good for 7 mo. I can't tell for sure when BT is, I'm guessing about 7:30 pm? You might try to push that morning nap out to 10:30 am, or 3 hr A time and then do the pm one starting at 2:30 pm, just so the day is a bit more even. But, I don't think the routine is the main cause of NWs.
For right now, while the tooth is coming through, I'd stop the PUPD at nap time. Either just hold him to sleep and lay him down, as he does good naps or try to settle him with shh-pat instead. For the NWs, I'm not sure how much you can do without ruling out some of those things that might be causing him discomfort. Is co-sleeping an option at all? It's not what we generally recommend at BW, but if it helps you get through this tough period and then you can work on getting him to self-settle once he's not hurting, it may be worth it for you to get some sleep. I would set up a mattress in his room though, so you wouldn't have to break the habit of him sleeping in your bed. What do you think?