DWV black water pipe cleanout question

The plumbing company that did my trenchless sewer lateral replacement is just finishing up the job. I haven't paid them yet. There's a few issues I'm concerned about. One is what appears to me an inexplicable failure to concrete over one ~2 square foot area next to a cleanout. That cleanout is covered by what a worker called a Christy box, which is a concrete and plastic conical cylinder with a circular concrete plastic covered top. They have put new concrete around one side, but not the other. I called and didn't get an answer on that one.
The other concern I have is a different cleanout. It's at grade level where an approximately 4 inch internal diameter black water drain pipe comes down the outside of the two story house. They have what I think you'd call a no hub connector that attaches the 4" drain pipe to their cleanout. I have two issues with this (and I'm no expert). The first is that the connector, which is around 4 inches long, is exposed black rubber with hose clamps on the ends and is above grade. Therefore it will get sunlight during a significant portion of the day. A book I have suggests that such rubber connectors are for below grade. Shouldn't they use a connector with stainless steel on the outside for the full length of the connector for this above ground application?
The other concern here is that the top of the cleanout there is below grade by 2". They have a rubber cap on the cleanout that you just pull off. Now, I was regrading the ground around the concrete they poured and the holes they'd dug to do the trenchless and I don't know what to do at this cleanout. If I add dirt to grade, the top of the cleanout (with the black rubber cap) will be almost 2" below grade and invisible. If I don't add that much dirt, the cleanout will be in a depression and be exposed to the elements, including sunlight. Shouldn't they do something different with that? I'd asked the foreman of the crew and he answered that they always do it like that, and I just said "OK." I wonder if I should mention this to the supervisor, who I'm going to call about the concrete work that wasn't done. Thanks for any information!

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.