Can my previous employer withdraw i140 by show casing some fraud reason?

An employer may withdraw/revoke an I-140 and its sponsorship of the I-140 for any reason or no reason at all. USCIS will then show the I-140...

Can she come back and do nekah again with me we have nekah before her green card?

Not, unless the documents of marriage contract/certificate were not filed with the mosque (masjid) and local government for record.

A person with an I-485 and appeal denied is accruing unlawful presence absent an underlying NIV status. An immigration attorney should consulted.

H1b and brother using credit card?

On H1b and brother using credit card should not effect the H1b visa status without active involvement. a consultation with an immigration attorney...

[H1B] Change employers while previous H1B transfer petition is still pending ?

An H1B employee may begin working with employer C filing an H1B change of employer petitions as soon as the the H1B transfer petition is receipted

A reentry permit is more likely approved than admission to the US after long absences.

one may write other names used in any way.

Can my husband be my joint sponsor for my parents because my income don't qualify for poverty guideline?

a husband may be a joint sponsor for one's parents green card because one's income don't qualify for poverty guideline..

I-140 approved 5 years ago and company filed chapter 11 bankruptcy recently?

An I-140 sponsored employee maintains the I-140 priority date for subsequent EB1,2,3 employer I-140 petitions and green card.

Can the cancellation of green card for a future spouse be included in a prenup agreement?

While one might enter an abandon / cancel green card into a pre-nup ... It isn't likely enforceable. But, if the marriage goes bad while in...