IBM is all in on the multi cloud story since they missed the cloud memo, and RH openshift is their key to allowing customers to lift and shift from AWS to Azure to GCP etc. Plus it's pretty clear they know how to do layoffs and that knowledge may be applied to RH soon to boost profitability.
You may well be right, indeed that was along the lines of my initial thought about this and would explain the size and scale of investment. Then if RH fails as they would currently to keep up those interest payments, then accountants can just rub their hands and use that debt to offset profits down the line.
Time will tell, certainly IBM has the kit and for years had its own dark fiber internet backbone globally, so have been well placed for years to capture the cloud market, yet failed to move on. Which for a company that saw a shift towards service offerings, was probably a big source of embarrassment internally at some levels.