"has been forced instead" is correct and usable in written English.
You can use it to describe a situation where, instead of one thing happening, something different has been made to happen due to external pressures or conditions. For example: "Although the original plan was to have a concert, it has been forced instead to be a virtual event due to pandemic restrictions."
She said she had joined a party that intended to resettle in Liberia, but after one of its members robbed her she had been forced, instead, to remain in Lynchburg, Va.
You could choose to take up the plight of a master swordsmith who, after the local gangsters squeezed his trade routes, has been forced to sell dumplings instead.
It should be celebrating its continued success this summer; instead it has been forced to suspend the service.
Instead, he has been forced to admit publicly that John Biggs, an economist and pension-fund manager who had been due to become the board's chairman, had not been offered the job after all.
Instead he has been forced to focus on trying to tighten EU nationals' entitlement to benefits, although the vast majority of Poles and Romanians are drawn to Britain by the prospect of jobs rather than hand-outs.
He would have liked to spend the summer bolstering his case for a critical autumn referendum on constitutional reforms he supports, but instead he has been forced to grapple with the banking issues.
Instead, it has been forced to resort to searching cars leaving Kunduz with hopes of finding the cleric under a stack of blankets or perhaps in someone's trunk.
Instead, the party has been forced to respond to a pervasive belief, backed by assertions by the Irish justice minister and the police, that its allies in the I.R.A. are behind widespread illegal activity, including a Belfast man's slaying in a bar fight with I.R.A. members five weeks ago.
Instead, they said, he has been forced to focus on tactical details, and not very effectively.
Instead of a flashy summer entrance, Prokhorov has been forced to take a conservative approach in rebuilding the Nets.
