Hi,
IITC is no longer a useful place to check as it is not up to date.
Use the map that tge wayfarer team provided and to aid its use search for community created tools - search wayfarer tools.
The observations on the mechanics about powerspots I believe still have gaps.
It appears to be that a certain number will be available to be active during a rotation. If yours is not active in the rotation it won’t be available to appear. When the next rotation happens it might be selected.
There is a clear numbers game in action if there are a lot of potential Powerspots to be selected from then it may take awhike for a specific one to appear. I had one that sat unused for many months before being selected.
I suggest you get to know your area and build up a picture of which points are becoming powerspots. And be patient. 
You were right before. WDD has a tool to compute that from the coordinates.
Tzwevepark (51.035202,3.204274) is an imported wayspot for use as a powerspot
[@cyndiepooh it isn’t showing on your screenshot - do you have some options turned off?]
I did not show their situation. I showed mine where only one eligible location is being used as a powerspot. I do see their import.
Apologies, thought I was replying to you, but was actually replying to a post from the op!
A while ago, Niantic did a batch import of wayspots for the sole purpose of creating powerspots. There were generally of things that would not be eligible as community-submitted wayspots and often on single-family private residential property. They don’t stop the community submitting wayspots for the same things (if eligible) as they don’t appear on the reviewing “nearby” map.
This was a one-off import. On the wayfarer map, these are marked as “Imported Wayspot” (the lower-right icon in the image below)

Okay so maybe I got confused trying to talk about two different issues. The other one does look like it should appear on the map when there is sync again.
Why did we say this was not the sync issue?
Also - you are using Pogo Tools, which won’t be accurate or up-to-date. Niantic Wayfarer was made available a few months ago and needs to be your go-to map of choice for Pokemon Go.
The initial post said this one was accepted in January, but the op had the two wayspot dates confused and had swapped them round.
This kind is considered street infrastructure instead of a trail marker, @iFrankmans gave me a useful link above
That is correct information to use going forward. But this seems to have been accepted by reviewers, and unless it is reported and removed, should show up when sync happens. If the Wayspot is removed, of course, then it won’t show up.
We do not have these kind of bike route markers in my part of the world, and I struggle to understand which are allowed to remain and which are removed when reported.
[Responding to the need to use the Wayfarer map because IITC is not up to date]
Help, I’m confused, do I have to if I updated the IITC map with coordinates and data from the wayfarer map. I live in a pretty rural area and checked the wayfarer map too. (I don’t have those purple circles when I use the wayfarer map btw?)
I started using IITC instead of a text to-do list. Months before the map came out. I knew it wasn’t up to date, but i used it as a starting point and added new info as I found reliable sources or nominated wayspots.
P.S. i checked the imported one, tzwevepark is far enough from “laat ons een bloem” but obviously too close to “Skate Plaza”. So tzwevepark would not be considered in the powerspot pool correct?
I’ll try to update if anything changes
The wayfarer map is accurate and up-to-date for wayfarer (and therefore Pokemon Go). Nothing else is.
You can do whatever you like, but it’s really not efficient to be manually copying and pasting Wayspot data from the Wayfarer map to the IITC map when you could just use the Wayfarer map.
You seem to have worked out how to install IITC so you could probably get similar sorts of functions set up in the Wayfarer Map with assistance. There are various Wayfarer communities who help users with those sorts of things on places like Discord or Reddit.