Thanks for pointing it out, We realize our mistake here. We also should've done proper attribution. Will be correcting this.
Otherwise, this idea is interesting and probably generalizable to other applications. Maybe it's not crystal clear to me, but what are the advantages of your service over existing solutions such as Nimbo and Spotty? FWIW it might be worthwhile adding this to your website.
Good luck!
The biggest advantage which was missing in the Open source options was monitoring on the training job and auto recovery from spot interruptions which spotML does.