I wish there was a dislike button. Who are you, and how much 1st hand experience with VB and other frames do you have?
Saying there is "no quality control whatsoever from velobuild" is simply false. I don't even want to argue, I just wish posts could be downvoted.

I'm sorry that you feel butthurt. It would certainly help the conversation if you could bring yourself to argue your point. Have you audited their production to know they are doing any QC? Are you sure you aren't conflating quality with quality control? In general you don't necessarily need any of the later to produce a decent product...

I've bought two frames from them, one perfect as you can only wish for, the other had a fork steerer tube that was 2mm(!!!) out of round, oval oversized pressfit BB (so you can't press in anything because you can just pull it out without any force), threads of the brake interfaces filled with resin, a seat tube that was only reamed out to about 7cm depth, voids on any machined surface and flaking paint right out of the box (that it wasn't painted as agreed upon should be a given at this point),.
The issues of that second frame are so obvious and present through the whole manufacturing process that I can't imagine even a rudimentary QC process to miss ALL of them and not pull that frame at some point from the production line before it reaches a customer.

I've audited enough production places to know the theme. They aren't evil, notice the defects and send them to the customers anyway - they just don't have dedicated processes set up so a defective product can be detected and pulled from the line at a later stage without incuring penalities to the person reporting the defects.
QC is a significant "non-productive" share of the production cost. If you can cut that, you'll be able to offer the product for cheaper. If your production is set up well in general, so the defect rate is low, you might even come ahead in customer experience on average.

Do these have any advantage over your normal SRAM RED 8-bolt Crankarms?
They seem to be the same weight and apparently only $20 cheaper.

While I appreciate the competition of Cybrei, Incolor and Lexon, am I jaded to expect at least a little more of a price gap considering the unproven durability and lack of local customer support/warranty?

I'm running Pirelli Cinturato Velo TLRs in 35mm (about 38mm on 25mm inner width rims) on my year-round commuting bike through everything badly maintained city roads have to offer (gravel, glass, potholes, ...). They sealed immediately and haven't leaked since, didn't get a puncture either. I give them air about every 2-3 month and the sealant inside is probably dry for ages (haven't refreshed it for two years...).

They are certainly not the fastest tire, nor do they offer above-average grip. I would still recommend them if you are just looking for a resilient, easy to mount and good sealing tire.

I don't have a source for a replacement top cap. I could probably model and print you one though, if you are located somewhere sending a package from Germany to is not outrageously expensive. You wouldn't be able to preload the steerer with it - you would have to use a normal round cap for that - but it should look pretty decent.
Is my assumption correct that the only thing broken is the chamfer interfacing with the screw?