GOVERNMENT JOB- NOC

Hi....i have been working in BHARAT ELECTRONICS LIMITED ( PSU) Navaratna company on fixed term for 1 year since November 2018....I have applied for a railway job (junior engineer post) in January 2019..while applying for the job I have mentioned that that Iam not working in any government job because I was working on fixed term basis.....now after completing my 1 year term ,I got the railway job ...........can I join in railway job ????will they come to know i have been worked in PSU Company before.... because I mentioned not working...i dont need to produce NOC to railway department......but can they object after joining if they come to know that i have worked.....is there any possibility of knowing that previously worked in a psu like through UAN &PF ACCOUNT DETAILS,PAN CARD, VIGILANCE,ITR(INCOME TAX RETURN) STATEMENT?????please reply thank you regards SRINIVASULU B