Paul,
Under the circumstances you did right to walk away.
However as Derek has intimated, an acidic cleaning agent may have been safe on these dyes.
I have frequently use an acid pre-spray as a dye stabiliser. This has enabled cleaning with a neutral or very mildly alkaline cleaner. The same dye stabiliser is then used as a post-spray to prevent dye bleed during the rapid-dry.
I would not have even considered Ultimate Master for these rugs.