Many employees like using company credit card for expenses. Its great if someone else tracks and pays all the bills! Kickbacks or legitimate rebates from vendors whose bills company paid? Got to be careful alleging a crime.
But asking you to apply for credit card, secured by your credit, to pay for company expenses? Maybe if they promptly reimburse. But if employer is intentionally slow in paying and it damages your credit you may well have a claim under WA (and possibly federal) law.