Yes, it's been suggested that Goering wanted Hitler to keep the panzers ets back out of the way, so that his Luftwaffe could destroy the British Expeditionary Force trapped at Dunkirk.
However, there is no evidence that such a plea was ever made.
(Perhaps the source of the rumour is the fact that, in 1942, Goering did prevail on Hitler to let the Luftwaffe save the cut-off German armies at Stalingrad, by supplying them from the air -- which H did agree to (it looked a better bet than surrendering to the Russians.)
Dunkirk was within easy reach of the British airfields on the south coast, and the RAF in fact made a very large contribution to the evacuation (Many of the air battles were fought out of sight of the Dunkirk beaches, so that the men of the BEF, queueing for hours up to their necks in water, 'Where's the bloody RAF?')
The evidence is that they did indeed want to. Hitler had been ordering Guderian to slow down for several days, but G continued his breakneck advance by sending out "scout-patrols", which met little opposition. But on 26 May, Hitler issued a direct unequivocal order to Guderian, to stop. G at this time had taken Calais and Gravelines (10 mi west of Dunkirk) and wanted to push eastwards, thereby squashing the BEF between himself and Army Group B which was driving in from the north-east.
We know now that there was nothing to stop Guderian from doing exactly that, so that Hitler's order now looks like the biggest blunder of the war. However, Hitler did not have that hindsight.
The best explanation why Hitler stopped Guderian is not that he wanted to give Goering his way, nor that the tanks could not advance over the muddy ground, nor that he thought the British, once gone, would never dare to come back.
The best explanation is that Hitler feared a strong French counter-attack from the south, which he feared might trap Guderian between the French and the BEF at Dunkirk. But the French forces in the area were in fact dug in around Dunkirk, and they contributed greatly to the evacuation -- most of them being themselves captured.
As early as 20 May, plans were made for evacuating small groups of stragglers from the Dunkirk area. It was considered that, with luck, as many as 45,000 could be brought home that way.
By 26 May, there was no other choice but Dunkirk. But the problem was the shallow water, and the big ships could not get in close. On 28 May, the call went out for 'small boats', to ferry the soldiers off the beach to the ships. An amazing 800 small boats, from as far away as Scotland, made the trip to Dunkirk.
On 29 May, Hitler finally unleashed Guderian to attack Dunkirk from the west. But the BEF (and the French) now had prepared defences, and were able to hold them up. On 29 May 47,000 were brought out; 30 May 54,000; 31 May 68,000. The operation ended 4 June, by which time an unbelievable 338,000 soldiers had been evacuated, including 224,000 British.
As we now know, of course there was no invasion. Many consider that it would never have succeeded anyway. Although the RAF was barely a match for the Luftwaffe, the hugely capable Royal Navy, in the Channel, was geared up to prevent exactly that.
If Britain had been invaded, or even had sought peace terms with Germany, who knows what that would have led to? The Dunkirk evacuation did not prevent invasion by itself -- but it helped.
Whatever Hitler's motive for the three-day delay, we should all give thanks for his priceless gift.
