To your 1st point, no. They are not just as likely to fold by resuming. Reason being, the TV money and sponsorship money they have already been paid, they would have to return, or at least sizeable chunks of it. This is hundreds of thousands of pounds to clubs lower down the ladder, but millions of pounds for most clubs up in the 92, more than enough to place them into administration. If the season resumes, that money would not have to be returned. If it's voided, it will.
To your 2nd point, you're assuming that Football will be played behind closed doors. It may well be, it may be that the authorities simply wait until it's safe to resume with crowds which could be quite some time. Who knows?! In any case, average gate receipts for 9 or 10 games (whatever is remaining for these clubs) are far, far lower than what they would lose by voiding and losing those sponsorship deals etc.
Resuming is absolutely the lesser of two evils for the majority of clubs, hence the strong reaction from those lower down the ladder to the decision to void the NL.