Is your current agent unable to answer these questions for you? If not, I'd be more concerned with the whole transaction that you're entering into than whether or not the first lien is going to accept your offer. If you're not getting the advice you need at this stage, alarm bells should be going off about the advice you've received prior to making the offer.
Having the 2nd accept is a good sign but doesn't mean the first will accept. It's normally the other way round as the first lien is in the best position whilst the 2nd often gets the bad end of the deal and is reluctant to take a hit.

Best of luck, Ken

This frequently happens, typically the first lien holders amount to be forgiven is a much larger amount so they are therefore more likely to take time and review the offers. Also many of the decision makers at primary lenders offices are carrying quite a load of short sales and foreclosures to deal with. It can be an agonizing process. It takes alot of patience on the part of the buyer and frequently alot of activity from the buyers agent. The lien holder will be looking at how much they will be writing off and what they can do to mitigate the loss as much as possible, private mortgage insurance policy, cost analysis of foreclosure, sellers ability to refinance & retain the property as well as the buyers ability to sometimes offer more or other offers with higher and better terms for the lender. Best of luck in your endeavor